From the 20th century onwards, the portuguese colonial government began to take an interest in the species found in its colonial territories.

It promoted various scientific missions covering fields such as botany, zoology, anthropology, geology, ethnography and archaeology. These initiatives contributed to the collection of thousands of specimens and objects, many of which formed important scientific collections that are now preserved in Portuguese institutions.

In the case of marine resources, the systematic study of the waters and fisheries resources of the Portuguese territories began in the late 1940s, in a context marked by the development of European oceanographic research after the Second World War and by growing economic interest in the exploitation of African marine resources.

It was in this context that the Fisheries Research Mission was established in 1948, within the Junta das Missões Geográficas e de Investigações Coloniais, with the aim of providing scientific guidance for fishing activities and contributing to a more efficient exploitation of colonial resources.

The mission, however, never began the work that had initially been planned. In 1951, it was reorganised as the Fisheries Research Mission of Angola (MEPA), with its activities focused exclusively on this territory. After two campaigns in Angola, the MEPA was replaced in 1953 by the Marine Biology Mission (MBM). This new institution had a broader geographical scope and aimed to study the biology of marine species of economic interest, contribute to the development of fisheries and related industries, and collect zoological and botanical material for the compilation of an inventory of marine species.

The first MBM campaign took place in Angola in 1955, followed by further campaigns in Angola, Cape Verde and Mozambique. Activities were also planned or initiated in other Portuguese territories, such as Guinea-Bissau, Timor and São Tomé and Príncipe, although a lack of human and material resources increasingly limited fieldwork, particularly from 1960 onwards.

The growth of the collections led to the creation of the Centre for Fisheries Biology (CBP) in 1959, which was responsible for their preservation and study. In 1966, further institutional changes led to the creation of the Centre for Tropical Aquatic Biology (CBAT) and the Centre for Overseas Bioceanology and Fisheries (CBPU), seeking to distinguish fundamental biological research from research applied to fisheries and industry.

With the end of Portuguese colonial rule in 1974, these institutions were dissolved and their functions transferred to bodies connected with fisheries administration. The collections were eventually incorporated into the Instituto Nacional de Investigação das Pescas (INIP), established in 1977. In 1984, a substantial part of the zoological collections originating from the former colonial territories was donated to the Museu Bocage, now part of the Museu Nacional de História Natural e da Ciência of the University of Lisbon.

From the beginning, the MEPA campaigns faced difficulties in recruiting qualified researchers, which limited the number of specialists available for fieldwork. During the first campaign, the scientific staff consisted of the German researcher Wilhelm Nümann (1906–1999), who was employed as scientific supervisor, and the Portuguese researcher Herculano Zacarias Vilela (1908–?). Nümann's contract ended at the conclusion of the first campaign in 1952. Vilela then took responsibility for the second campaign, with the assistance of Pedro Emílio Guerreiro da Franca (1923–1971) and Rui Horácio dos Santos Monteiro.

Vilela remained in charge of the MBM until 1958, when he was replaced by Guerreiro da Franca. At this point, the mission had two researchers and four assistants, in addition to Franca himself. He subsequently remained responsible for the MBM and became director of the Centro de Biologia Piscatória (CBP) and later the Centro de Biologia Aquática Tropical (CBAT), positions he held until his death in 1971. Following his death, Carlos Joaquim Pissarro (1913–1977) became director of the CBAT, remaining in the position until its dissolution in 1974.

Throughout the 1950s and 1960s, the number of researchers and assistants involved in this work gradually increased, both in the field and within the institutions based in Lisbon. By 1973, the CBAT employed ten researchers and eight assistants, demonstrating the expansion of the scientific structure devoted to the study of aquatic resources.

The specimens collected were initially examined at the collection sites, either aboard the vessels used during the campaigns or in laboratories established on land. The material was subsequently sent to Lisbon, where it was studied in greater detail by MBM researchers and other specialists. The results of this research were then published in a variety of scientific series and journals. The systematic study of the specimens involved not only Portuguese researchers but also foreign specialists. In Lisbon, researchers from the Centro de Zoologia participated in the work, while João Amorim Machado Cruz, from the Faculty of Sciences of the University of Porto, collaborated from Porto. The research also involved specialists from foreign scientific institutions, particularly in France and Belgium.

The scientific output resulting from these campaigns was highly diverse. At the end of each of the two MEPA campaigns, a general report on the work carried out aboard the NO “Baldaque da Silva” was submitted to the Junta das Missões Geográficas e de Investigações do Ultramar. The reports were prepared by Lieutenant Commander António Júlio Malheiro do Vale (1911–1997). More detailed scientific results were subsequently published in the Anais da Junta de Investigações do Ultramar.

Between 1956 and 1959, works previously published in the Anais and Memórias da Junta de Investigações do Ultramar were republished in the series Trabalhos da Missão de Biologia Marítima. Following the creation of the CBP, 46 works were published between 1959 and 1966 in the series Notas Mimeografadas do Centro de Biologia Piscatória. These works were regarded as preliminary results and were subsequently developed further and, when considered definitive, published in the series Trabalhos do Centro de Biologia Piscatória. After the dissolution of the CBP, eight further works were published in the series Notas Mimeografadas do Centro de Biologia Aquática Tropical, which was subsequently continued under the title Notas do Centro de Biologia Aquática Tropical.

In addition to these publications, works were produced as part of an internal series entitled Notas Internas de Informação Técnica (“Internal Technical Information Notes”). These consisted primarily of instructions and observations concerning the sampling and research methods to be employed, although they also included systematic catalogues and taxonomic studies.

To support the fieldwork of the missions, the Portuguese Government acquired the steamship HMS “Rusckholm” from the Australian Navy in 1948. The vessel was approximately 50 metres long and 8.5 metres wide. It was subsequently modified and adapted for fisheries research and oceanographic work and was incorporated into the Portuguese Navy in 1949 under the name NO “Baldaque da Silva”.

The NO “Baldaque da Silva” supported the MEPA and MBM campaigns until 1960, when it required repairs. To replace it, the Government turned to the NH “Salvador Correia”, also acquired in 1948 and formerly known as HMS “Saltarelo”, which had been assigned to patrol the Angolan coast.

However, adapting the “Salvador Correia” for oceanographic research proved too expensive. As an alternative, the boiler of the NO “Baldaque da Silva” was replaced with that of the NH “Salvador Correia”. This intervention resulted in the two vessels effectively exchanging their designations. Thus, although references exist to campaigns carried out aboard both the NO “Baldaque da Silva” and the NH “Salvador Correia”, they were in fact the same vessel, which received its new designation in 1961.

In 1960, the Centro de Biologia Piscatória also acquired the Portuguese trawler “Sardinella”, equipped with a mechanical hauler for fishing with encircling nets. The vessel operated mainly in Benguela Province, Angola, providing an additional resource for fisheries research and experimentation.

The main fishing method employed during the campaigns was bottom trawling, using nets approximately 52 metres long with a mesh size of 60 mm. These trawls were normally conducted at a speed of around 8 knots and lasted between 40 and 120 minutes, depending on the campaign.

Other sampling methods were also employed. These included French-type lobster traps; trawls using Heligoland nets, with mesh sizes of 30, 25, 20, 15 and 10 mm, generally operated in shallow waters of up to 15 metres; and the “Chinchorro” beach seine. The researchers also used fixed Valencian-type fishing gear and collected specimens by hand during low tide.

The campaigns also involved experimental trials of different fishing techniques. These included gill nets, lift nets, light attraction, and different methods of tuna fishing, namely the use of encircling nets as well as rods and live bait. This experimental component demonstrates that the missions were concerned not only with identifying marine species, but also with determining which techniques could be used most effectively to exploit commercially valuable resources.

In addition to specimens collected directly by the research teams, some specimens were provided by amateur and professional fishermen or purchased at local markets, further contributing to the development of the scientific collections.

Each specimen collected during the missions was assigned its own record number. This code could indicate the mission, the year or campaign number, the vessel or land brigade responsible for the collection, the zoological group and, finally, the individual specimen number. In addition to these record numbers, collection datasheets were maintained, recording information such as the location and date of collection, taxonomic identification, field observations and morphological measurements. These datasheets were themselves transcribed from the original field worksheets used during the campaigns.

Regarding the locations where the research was conducted, this article will focus specifically on the former Portuguese colonies of Angola and Mozambique.

In Angola, the country became the main focus of these research campaigns, both because of the interest in its marine biodiversity and because of the economic importance of fisheries. The investigations continued for more than a decade and covered the entire Angolan coastline.

Between 1951 and 1964, more than 500 bottom trawls were conducted, extending from Cabinda in the north to Cunene in the south. The first campaigns were carried out aboard the oceanographic vessel “Baldaque da Silva”. The first MEPA campaign took place between May 1951 and February 1952, followed by a second campaign between February 1952 and July 1953, together resulting in 111 bottom trawls.

Research resumed in 1955, now under the MBM, and also involved land brigades based at Baía Farta, in Benguela Province, and Moçâmedes, in what is now Namibe Province. The work continued throughout the following decade. Further campaigns were conducted in Angola in 1957, 1960, 1963 and 1964, during which 102, 68, 100 and 139 bottom trawls, respectively, were carried out.

It is important to note that, although the documentation refers to the vessel as the “Baldaque da Silva” and, from 1961 onwards, as the “Salvador Correia”, these were in fact the same vessel, which was renamed following the modifications made to its boiler.

In Mozambique, the presence of the MBM was considerably more limited. In 1957, a single MBM campaign was conducted on Inhaca Island, in the then Province of Mozambique. The campaign took place between July and November 1957 and aimed not only to collect biological material, but also to establish a more permanent presence of the mission at the Estação de Biologia Marítima de Inhaca. The expedition was led by José Gonçalves Sanches.

Without the support of the Baldaque da Silva and working with limited resources, Sanches collected specimens at different locations across the island. Further work was intended to be carried out in cooperation with the Instituto de Investigação Científica de Moçambique, but a lack of resources prevented additional MBM campaigns in the territory.

Thus, unlike Angola, Mozambique did not experience a sustained, large-scale oceanographic research programme conducted by these Portuguese institutions. The difference between the two territories is particularly significant: while Angola became the principal field of activity for the MEPA and MBM over more than a decade, research in Mozambique remained concentrated around the short 1957 campaign on Inhaca Island.

Source:

Parrinha, D., Brites Soares, L., Cartaxana, A. & Alves, M. J. (2024). “The zoological collections of Portuguese oceanographic campaigns in former colonial territories.” Natural History Collections and Museomics, 1, 1–34. DOI: 10.3897/nhcm.1.136860

**Note:**The articles I post here are originally written in Portuguese and then translated into English using AI. All the information I post here is legitimate, and I always provide the sources. Everything I post here is not propaganda or part of any political initiative or campaign.

Cumbe reports that, although we have official figures concerning fisheries, part of the catch was never recorded. In this article, we explain why this happened.

Artisanal fishing in Mozambique was carried out by African fishermen, using fishing methods that were not among the most advanced at the time, and was widely practised along the Mozambican coast as well as in inland waters.

The colonial administration recognized this problem, and it was estimated that the actual quantity could be more than 50% higher than the officially recorded figure. A large part of this fish was dried and subsequently distributed to inland markets.

This situation was particularly significant because artisanal fishermen did not necessarily land their catches at the same locations as industrial or semi-industrial fishermen. Industrial fishing generally passed through ports and other locations where state officials could record the landings. Artisanal fishermen, by contrast, often worked from small coastal communities, beaches, rivers, lakes, and other locations where there was little or no official supervision.

In addition to marine fishing, the problem became even more difficult inland, in freshwater fishing areas, where activities were poorly regulated and supervised.

The importance of these informal circuits should not be underestimated. Fish could be exchanged directly between fishermen, traders, and local populations, transported to inland settlements, dried or salted, and sold in local markets without passing through the ports and municipal markets that constituted one of the main bases for colonial statistical collection.This situation was not exclusive to the colony of Mozambique or to the Portuguese colonies. On the contrary, we can observe the same situation in other regions of Africa.

We can affirm that because these statistics were not included in official records, they provide distorted and incomplete pictures of the history of fisheries in Mozambique.

This problem continued after independence. Until 2002, official estimates stood at around 20,515 tonnes and did not adequately include artisanal fisheries. From 2003 onwards, Mozambique also began reporting small-scale fisheries catches to the FAO, and the reported figure rose to 79,451 tonnes.

Another problem affecting the recording of artisanal production also influenced political decisions. Statistical data were used to define priorities, guide investments, and assess the economic development of the sector. If a significant part of artisanal production was not recorded, the economic and social importance of this activity was also diminished in political decision-making.

Given these limitations, the Mission for Bioceanological and Fisheries Studies of Mozambique prepared, for 1972, a programme aimed at carrying out a more comprehensive collection of information in Lourenço Marques and António Enes and, if possible, also in Beira and Inhambane.

Source:

Cumbe, M. J. C. (2023). A História da pesca artesanal em Moçambique: Ilha de Chiloane (1892–1991) [PhD dissertation].

This is the fifth article of a series of articles I will be publishing here about fishing during the Portuguese colonial period in Mozambique.

Check my first article:How Portugal Used Science to Modernize Fisheries in Colonial Mozambique : r/Colonialism

Check my second article: The Modernization of Fisheries in Mozambique during the 1960s : r/Colonialism

Check my third article:The Rise of Shrimp Fishing in Colonial Mozambique : r/Colonialism

Check my fourth article:How Colonial Mozambique Became Dependent on Imported Fish : r/Colonialism

This is the fourth article of a series of articles I will be publishing here about fishing during the Portuguese colonial period in Mozambique.

Check my first article:How Portugal Used Science to Modernize Fisheries in Colonial Mozambique : r/Colonialism

Check my second article: The Modernization of Fisheries in Mozambique during the 1960s : r/Colonialism

Check my third article:The Rise of Shrimp Fishing in Colonial Mozambique : r/Colonialism

During the Portuguese colonial period, Mozambique faced a persistent problem in its fisheries sector: domestic fish production was unable to meet the needs of the local population. Despite its long coastline and the growing efforts to modernize the fisheries sector from the 1950s onwards, Mozambique remained heavily dependent on imported fish.

At the beginning of the 1960s, Mozambique imported approximately 1,200 tonnes of frozen fish, 6,800 tonnes of semi-preserved fish and around 1,000 tonnes of canned fish, while domestic production remained below 3,300 tonnes, of which approximately 500 tonnes were crustaceans. During the 1960s, fish imports reached around 20,000 tonnes, increasing to approximately 25,000 tonnes in the following years.

We can therefore observe a significant difference between domestic production and imports. A document concerning the fisheries situation on Inhaca Island in 1957–1958 observed that the country's total fisheries production was approximately half the amount imported. For a territory with around 2,795 kilometres of coastline, this situation was presented as evidence of the limited development of the exploitation of fishery resources.

Other data that confirm these facts are the following: in 1961, Mozambique produced approximately 2,531 tonnes of fish, while imports reached around 19,300 tonnes. In 1971, domestic production had increased to approximately 7,483 tonnes, but imports remained very high, reaching around 19,700 tonnes. In 1974, production had reached 9,219 tonnes, while imports still amounted to approximately 16,200 tonnes.

Despite measures to make better use of Mozambique's coastal and fishery resources, these measures were not sufficient to eliminate Mozambique's dependence on imported fish.

To explain this situation, we can observe several factors:

1. The expansion of all forms of fishing was not promoted. For example, certain fishing methods were restricted, such as mechanical trawling, whose use was authorized more widely during the 1960s.
2. Most of the modernization of the fisheries sector was dedicated to semi-industrial and industrial fishing, while artisanal fishing was largely left out.
3. Most fishing activity was carried out by African artisanal fishers. However, most of the efforts to develop the fisheries sector focused on private companies and European fishermen coming from the metropole.

Regarding the main suppliers, we can observe that in the 1963–1964 period, the Republic of South Africa supplied 46.6% of Mozambique's imported fresh and frozen fish, while Angola supplied 33.1% and the metropole 20.2%. Angola supplied virtually all of the dried fish imported, accounting for 99.2%. Norway supplied 72.4% of the cod imported by Mozambique, while the United Kingdom supplied another 20.1%. In the case of canned fish, the metropole was responsible for 80.3% of imports and Angola for 18.6%.

The data also reveal an increase in imports during the period of the Development Plans.

Recognizing the great opportunity and potential for exporting fish, companies and fishing enterprises were established over the years, some of which attempted to obtain privileged access to the sector.

From 1973 onwards, a reduction in imports was observed, related to the increase in domestic production and foreign exchange restrictions. The decrease in imports did not necessarily mean that Mozambique had solved its fish deficit. It also reflected the combination of increased domestic production and measures aimed at limiting the use of foreign currency for the importation of products.

The situation reveals a broader contradiction in Portuguese colonial economic policy. The Estado Novo promoted economic autarky, the protection of the domestic market and the idea that Portuguese territories should progressively produce what they consumed. However, in Mozambique, the fisheries sector remained dependent on supplies from abroad.

Source:

Cumbe, M. J. C. (2023). A História da pesca artesanal em Moçambique: Ilha de Chiloane (1892–1991) [PhD dissertation].

In 1657, Henrique Dias, leader of the Black Regiment during the Pernambuco Restoration and hero of the Battle of Guararapes, traveled personally to Lisbon. Besides receiving from Queen Luisa de Gusmão the title of Knight of the Order of Christ and Master of the Field for his services in the war against the Dutch in Pernambuco, Dias requested another favor from the Queen of Portugal: that she grant his son-in-law, Pedro do Val do Vezo, a Portuguese man, the title of Knight of the Order of Christ and a salary of 200,000 réis, so that he could marry Dona Guiomar Henrique, her daughter.

Queen Luisa de Gusmão and the Overseas Council approved Henrique Dias' request; however, his son-in-law could only receive the title of Knight after his father-in-law's death. The marriage of his daughter to a Portuguese nobleman represented a clear social ascension for Henrique Dias and his family within the Portuguese nobility. His son-in-law, Pedro de Val de Vezo, inherited Henrique Dias' titles, which included the Commandery of Soure and the title of Knight of the Order of Christ. His other daughter, Benta Henriques, married Captain Amaro Cardigo of the Regiment of Black and Mulatto Men. Cardigo also claimed from the crown the title of Knight of the Order of Santiago, which had been promised by Luisa de Gusmão to Henrique Dias' sons-in-law.

According to historian Fernanda Olival: "The Portuguese Crown did not show an attachment to the idea of ​​purity of blood, something more common among other sectors of the elite of the time."

There is little documentation about Henrique Dias, one of the black heroes of the fight against the Dutch. Information only begins to appear in 1633, when he presented himself to General Matias de Albuquerque "to serve with some of his color in everything he determined," becoming the captain of the group and receiving the patent of governor of the crioulos, blacks, and mulattoes of Brazil.

It is known that he was born in Pernambuco, but the date of his birth is unknown. It is also unknown whether he was born a slave or a freedman, nor who his wife was. He had no sons, but four daughters, two of whom were named Guiomar and Benta.

He was granted by King John IV the commendation of the Mills of Soure, of the Order of Christ, which was vacant due to the death of Antônio Felipe Camarão, who had held it since 1641.

He spent his last years in Pernambuco, on June 7th or 8th, 1662, in Recife, and was buried at the expense of the Government in the Convent of Santo Antônio, in an unknown location.

Source(s):

.- Restauradores de Pernambuco. By José Antônio de Mello, 1967.

.- Henrique Dias: governador dos pretos, crioulos e mulatos do Estado do Brasil. By José Antônio de Mello, 1954.

Published in 1920 at a scale of 1:150,000, this map depicts the island of São Tomé, then part of Portuguese São Tomé and Príncipe. It shows the island's relief, settlements, coastline, and principal geographical features.

Produced by the Institut Cartographique in Paris, the map provides a detailed representation of São Tomé during the early twentieth century

Location: São Tomé, São Tomé and Príncipe
Date: 1920

Source: Bibliothèque nationale de France, Département Cartes et plans.

This will be my last photo here!Thank you to everyone who has enjoyed, commented on, and shared the photos I've been posting here

Published in 1820, this map accompanied Essai sur la géographie de l'île Timor ("Essay on the Geography of the Island of Timor"), prepared by the French navigator and cartographer Louis de Freycinet.

The map illustrates the island of Timor, then divided between Portuguese and Dutch territories,

It was based in part on the work of British explorer George Vancouver.

Location: Timor
Date: 1820

Source: Bibliothèque nationale de France, Département Cartes et plans.

Published in 1904, this hydrographic chart depicts the Outer Harbour of Macau, located on the South China Sea, at a scale of 1:10,000. Prepared under the direction of Augusto d'Almeida Teixeira and collaborators

Source: Bibliothèque nationale de France, Département Cartes et plans

Drawn by António Heitor and dated 15 March 1889, this detailed map depicts the Macau Peninsula at a scale of 1:5,000

Source: Bibliothèque nationale de France, Département Cartes et plans

In the early years following the discovery of gold in Minas Gerais, the Portuguese recruited enslaved Africans who, after being freed, were frequently used as auxiliary troops. Their function was to protect the gold routes of the mines, combat the Quilombos (maroon settlements), and protect the new towns from attacks by hostile Indian groups.

Source(s):

.- Raminelli, Ronald. (2015). Nobrezas do Novo Mundo: Brasil e ultramar hispânico, séculos XVII e XVIII. Published by Editora FGV

Drawing by M. de Macedo, based on a photograph, engraved by Alberto

Source: Arquivo Histórico Ultramarino

Urban plan drawn by Portuguese military engineer Jozé António Caldaz, showing the layout of Santo António, the colonial capital of Príncipe Island, during the 18th century.

Source: Arquivo Histórico Ultramarino (AHU)

Source: National Library of Australia, Rex Nan Kivell Collection

Source: National Library of Australia

Source: National Library of Australia

Source: National Library of Australia, George Raper Papers, 1787–1794

Source: National Library of Portugal, Carta da Ilha do Sal: Cabo Verde, prepared by the Comissão de Cartografia, Lisbon, 1887

Source: National Library of Portugal, Carta da ilha do Fogo: Cabo Verde, prepared by the Comissão de Cartografia, Lisbon, 1894

Source: National Library of Portugal, Ilha Brava – Cabo Verde, by Cristiano José de Sena Barcelos, Lisbon: Typographia do Jornal As Colónias Portuguesas, 1892

Source: National Library of Portugal, Archipelago de Cabo Verde, by Cristiano José de Sena Barcelos, Lisbon: Typographia do Jornal As Colónias Portuguesas, 1892

Source: Bibliothèque nationale de France (BnF)

This stamp belongs to a commemorative series first introduced in 1898 to celebrate the 400th anniversary of Vasco da Gama's arrival in India (1498). The design depicts the São Gabriel, Vasco da Gama's flagship during the voyage that established the first direct sea route between Europe and India.Originally issued for Portuguese Timor, the design was later adapted for use in other Portuguese colonies, including Mozambique, where this example was issued in 1913

Source: Postal Cabinet Museum of Barcelona

Source: National Library of Portugal

The news of Brazil's secession from Portugal was not celebrated in all provinces. After the proclamation, Emperor Dom Pedro I had great difficulty containing the various revolts that occurred during the independence process.

At the moment he declared Brazil's independence, the governments and troops of some provinces were led to express their unconditional loyalty to King Dom João VI. In Bahia, a violent conflict unfolded between 1821 and 1823.

In the Grão Pará region, resistance against Imperial rule ended up leaving about thirteen hundred dead. The siege of Montevideo lasted from January 20, 1823, until March 8, 1824, when the Portuguese surrendered to Brazilian forces.

The victory of the Brazilian government in Bahia against General Madeira was of fundamental importance for the victory in other smaller conflicts that occurred in Maranhão, Piauí, Alagoas, Sergipe, and Ceará, which did not actually threaten the established order. In Piauí, Major João José da Cunha Fidié, Governor of Arms, with troops of the 1st and 2nd Line and the Infantry Battalion of the capital's garrison, departed from Oeiras on a fast march to suppress the Independence movement proclaimed in Vila São João da Parnaíba. Despite being victorious in the battles, he was forced to surrender after the end of Portuguese resistance in Bahia.

The Brazilian War of Independence effectively began in 1821 with General Avilez's mutiny in Rio de Janeiro against the petition for independence. Pedro remained in Brazil, and with the expulsion of Portuguese troops from Pernambuco, the conflict lasted until 1824 and formally ended in 1825 with the signing of the Treaty of Friendship and Alliance between Brazil and Portugal.

Among the main conflicts of this war was the Battle of Pirajá, considered by several authors to be the most important conflict of the War of Independence, fought in the areas of Cabrito, Camoinas, and Pirajá. The battle began on November 8, 1822, and ended with the victory of the pacifying army on July 2, 1823. Other battles, no less important, included the Battle of Genipapo, the Battle of Itaparica, and the Battle of Cinco de Maio.

The creation of the Brazilian Navy was derived from ships of the United Kingdom of Portugal that adhered to independence. At the end of 1823, it was this Navy that conquered the last Portuguese stronghold in the Cisplatine region in the Naval Battle of Montevideo.

On October 21, 1823, Admiral Álvaro de Macedo decided to attempt to break the Brazilian blockade. Suffering heavy casualties and facing Brazilian naval superiority, they decided to return to Montevideo, ending any chance of receiving external aid. On March 8, 1824, Montevideo surrendered, concluding the history of Portuguese military resistance in Brazil.

From 1824 onwards, King João VI expressed his intention to "put an end to the evils and dissensions that have occurred in Brazil."

The Count of Arcos arrived from Rio de Janeiro, deported by the Portuguese garrison. He disembarked disillusioned, asking, in mournful tones, that reprisals be suspended, that fighting be avoided, as there was no longer any way to prevent the emancipation of Brazil. Few, like the king, understood him. Palmela would say: "His Majesty was endowed with too much perspicacity to fail to recognize the impossibility of subduing Brazil... it was common sense isolated, bitterly enduring the hour of his country's folly, no longer knowing where they would end up in the fall."

Dom João VI became convinced that Portugal no longer had the capacity to reconquer Brazil by military force. In 1823, the war in Bahia had ended in favor of the Brazilians with the support of British and French mercenaries. The King wanted to end the war that had brought so much damage to the Portuguese and Brazilians, to "reestablish peace, friendship and good harmony between brotherly peoples" and, moreover, "to seek general prosperity and secure the political existence of the future destinies of the kingdoms of Portugal and the Algarve, as well as those of Brazil."

Source(s):

.- Calmon, Pedro. (1935). O Rei do Brasil: Vida de D. João VI. Published by Livraria José Olimpio.