Mortalium animos (English: The minds of mortals) is a papal encyclical promulgated in 1928 by Pope Pius XI on the subject of religious unity, condemning certain presumptions of the early ecumenical movement and confirming that the unique Church founded by Jesus Christ is the Catholic Church.
Pope Pius XI, born Ambrogio Damiano Achille Ratti (31 May 1857 – 10 February 1939), was head of the Catholic Church from 6 February 1922 to his death in 1939. He was the first sovereign of Vatican City from its creation as an independent state on 11 February 1929. He assumed as his papal motto "Pax Christi in Regno Christi," translated "The Peace of Christ in the Kingdom of Christ."
