Maria I of Portugal Author:Frederic P. Miller, Agnes F. Vandome, John McBrewster Maria I (December 17, 1734 - March 20, 1816) was Queen of Portugal and the Algarves from 1777 until her death. Known as Maria the Pious, Maria the Mad, she was the first undisputed Queen regnant of Portugal. She was the eldest of the four daughters of Joseph I of Portugal and Mariana Victoria of Spain.