Pope Pius IX (1792 - 1878)

Pope Pius IX (Italian: Pio IX, pronounced Pio nono; born Giovanni Maria Mastai Ferretti; 13 May 1792 – 7 February 1878) was head of the Catholic Church from 16 June 1846 to his death on 7 February 1878. He was the longest-reigning elected pope, serving for over 31 years. During his pontificate, Pius IX convened the First Vatican Council (1869–70), which decreed papal infallibility, but the council was cut short owing to the loss of the Papal States.