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.
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.