Lisbon Regicide
The assassination of King Carlos and the Prince Royal was the effective end of a constitutional monarchy in Portugal (later confirmed by the 5 October 1910 revolution). The regime functioned for another 33 months with growing agitation and demands for reform (although considerably less than in the future First Republic). It cannot be denied that the weak and permissive attitude in the Government of Acclamation was an incentive for the Republican Party to attempt another coup. The assassinations did not change the system of government; instead, they delayed the change.
House of Aviz
Joaquim Veríssimo Serrão, writing in 1956 and counting António as a king, dates the end of the dynasty's rule of Portugal as occurring in 1581–1582. The Cortes of Tomar had acclaimed Philip II of Spain as Philip I of Portugal in 1581, subsequently António's forces were utterly defeated at sea by Álvaro de Bazán at the Battle of Ponta Delgada off São Miguel Island in the Azores, on 26 July 1582. António then retreated to Terceira, where he supervised the raising of levies for defense, but in November he left Angra do Heroísmo en route to France to persuade the French to furnish more troops, 800 of which arrived in June 1583. Philip had despatched Santa Cruz with an overwhelming force which left Lisbon on 23 June, and reaching sight of São Miguel some time after 7 July, finally reduced the Azores to subjection.