History of Portugal (1834–1910)
Militant Republicans and their allies in the Carbonária were not willing to remain in the shadows of the constitutional monarchy. Between 4–5 October 1910, members of the Carbonária, republican youth, and elements of the army instigated a coup d'état against the already weak constitutional monarchy. The young king and his family, after a few miscues, escaped from the Palace in Mafra to exile in England. On the morning of 5 October 1910, the Republic was declared from the balcony of Lisbon City Hall, ending eight centuries of monarchy in Portugal.
United Kingdom of Portugal, Brazil and the Algarves
With the death of the Portuguese King John VI on 10 March 1826, his heir apparent, Brazilian Emperor Pedro I, inherited the Portuguese Crown, and reigned briefly as King Pedro IV. On 20 March 1826 the proclamation of the Brazilian Emperor's accession to the Portuguese Throne was made public by the Portuguese Council of Regency (that had been instituted by King John VI during his final illness, and that was led by the Infanta Isabel Maria, daughter of John VI and Pedro I & IV's sister). With this union of Crowns, the monarchies of Portugal and Brazil were once again briefly united, but there was no thought of a reunification of the two separate States. Accordingly, this brief union of Crowns in the person of Pedro I and IV remained always a personal union only, and not a real union or a rebirth of the United Kingdom.