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.
History of Portugal (1777–1834)
Portugal's neighbor Spain, during its resistance to the Napoleonic invasions, had approved a liberal Constitution when King Ferdinand VII was in exile, but it was quickly abrogated on his return, and he reigned as absolute monarch. The Spanish model also served as an example for the Portuguese: a popular uprising in the provinces against absolutism forced the Spanish monarch to reinstate the 1820 Constitutional monarchy.