The descendants of John VI of Portugal, from the main branch of the House of Braganza, are present in several royal families across Europe and Brazil. Through his second son, Miguel I, some of his descendants have become rulers in Belgium, Luxembourg, and Liechtenstein, while others have been claimants to the thrones of Portugal, Austria-Hungary, and the former Duchy of Parma. Constitutional amendments regarding succession led to disputes throughout the nation following John VI's death.
John VI was born on May 13, 1767 in Lisbon, as the second son of Maria I and Pedro III. On May 8, 1785, John VI married Carlota Joaquina of Spain. They remained married until his death, and had nine children.
John VI became heir to the Portuguese throne in 1788, after his brother, José, Prince of Brazil, died of smallpox.
In 1799, John VI became the prince regent for his mother, Maria I. Spain and France soon declared war and invaded Portugal under Napoleon Bonaparte, initiating the War of the Oranges. Although peace was attained, the Portuguese Empire suffered major territorial losses as a result.
In 1807, the French Army invaded Portugal during the War of the Fourth Coalition. To avoid conflict, John VI relocated the Portuguese court and capital to colonial Brazil. John VI then elevated Brazil to the status of a kingdom to form the United Kingdom of Portugal, Brazil, and the Algarves.
John VI established his court in the city of Rio de Janeiro. When his mother, Maria I of Portugal, died in 1816, John VI was named king of the United Kingdom of Portugal, Brazil, and the Algarves. By that time, Napoleon had been defeated at the Battle of Waterloo, and the European courts demanded the return of the Portuguese court to Europe. John VI complied with the demands, leaving his son Pedro, later Pedro I of Brazil, as regent. Pedro later declared the independence of Brazil.
John VI's death in 1826 triggered a succession crisis over the Portuguese throne, with succession disputed among John VI's eldest sons and his granddaughter. This resulted in a split of the House of Braganza into three branches: the Portuguese House of Braganza, the Brazilian House of Braganza, and the Miguelist House of Braganza.