Pope Gregory XVI (Latin: Gregorius PP. XVI; Italian: Gregorio XVI; born Bartolomeo Alberto Cappellari; 18 September 1765 – 1 June 1846) was head of the Catholic Church and ruler of the Papal States from 2 February 1831 to his death in June 1846. He had adopted the name Mauro upon entering the religious order of the Camaldolese. He is the most recent pope to take the pontifical name "Gregory", the last to govern the Papal States for the whole duration of his pontificate, and the most recent not to have been a bishop when elected.
Reactionary in tendency, Gregory XVI opposed democratic and modernising reforms in the Papal States and throughout Europe, seeing them as fronts for liberalism and laicism. Against these trends, he sought to strengthen the religious and political authority of the papacy, a position known as ultramontanism. In the encyclical Mirari vos, he pronounced it "false and absurd, or rather mad, that we must secure and guarantee to each one liberty of conscience". He encouraged missionary activity abroad and condemned the slave trade, which at the time of his pontificate was increasingly suppressed.
