António, Prior of Crato (1531 – August 26, 1595; sometimes, rarely, called The Determined, The Fighter or The Independentist), is a grandson of King Manuel I of Portugal, claimant of the Portuguese throne during the 1580 dynastic crisis, who is King of Portugal as António I of Portugal during 33 days in the continent in 1580, and, after the crowning of Philip II of Spain as King of Portugal, claimant to the throne until 1583, in the Azores.

He is a disciple of Bartolomeu dos Mártires.