The present Constitution of Portugal was adopted in 1976 after the Carnation Revolution. It was preceded by a number of constitutions including ones created in 1822 (following the Liberal Revolution of 1820), 1838 (after the Liberal Wars), 1911 (following the 5 October 1910 revolution), and 1933 (after the 28 May 1926 coup d'état).
The Portuguese Constitution of 1933 was introduced by Prime Minister António de Oliveira Salazar in 1933, establishing the basis of the authoritarian Estado Novo regime, following the 28 May 1926 coup d'état. It is credited as the first constitution of any recognized country embracing corporatist principles (though predated significantly by the Charter of Carnaro), espousing a bicameral parliament, including a western-styled National Assembly, elected directly every four years, and the Corporative Chamber, representing different "corporations", schools, universities, colonies and local municipalities, in effect appointed by the National Assembly after its inaugural. The role of the Corporative Chamber was limited to that of an advisory body, while all legislation was handled by the Assembly under the direction of its only party or "movement", the National Union, an ideology-lacking beacon completely subordinate to the Salazar administration. The Constitution also stipulated for a strong President of Portugal, naming the Prime Minister on his own accord with no deference to the opinions of the Assembly required to be taken into consideration, such President to be elected every five years through direct elections with no term limits. Óscar Carmona served as President, although outmaneuvered politically by Salazar, until his death in 1951. The two following presidents, Craveiro Lopes and Américo Tomás, were more or less puppets of an aging Salazar, although the latter did not hesitate to use his wide-ranging powers to prevent Salazar's successor, Marcelo Caetano from performing changes aimed at reforming Portugal's authoritarian government. The direct consequence was the coup d'état of 1974.