The Order of St. Gregory the Great is established by Pope Gregory XVI of the Vatican State to recognize high support for the Vatican or for the Pope, by a man or a woman, and not necessarily a Roman Catholic.

The Pontifical Equestrian Order of St. Gregory the Great was established on 1 September 1831, by Pope Gregory XVI, seven months after his election as Pope.

Pope Gregory XVI 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.

Vatican City, officially the Vatican City State, or Vatican, is a landlocked sovereign state and city-state. It is an enclave within Rome, seat of the Catholic Church, and serves as the administrative centre of the Catholic Church. It became independent from the Kingdom of Italy in 1929 with the Lateran Treaty. Vatican City is governed by the See of Rome, commonly known as the Holy See, itself a sovereign entity under international law, which maintains its temporal power, governance, diplomacy, and spiritual independence. Vatican is also used as a metonym for the Holy See, which is the central governing body of the Catholic Church and Vatican City, comprising the pope and the Roman Curia.

The Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with 1.27 to 1.41 billion baptized Catholics worldwide as of 2025. It is among the world's oldest and largest international institutions and has played a prominent role in the history and development of Western civilization. The Church consists of 24 sui iuris (autonomous) churches, including the Latin Church and 23 Eastern Catholic Churches, which comprise almost 3,500 dioceses and eparchies around the world, each overseen by one or more bishops. The pope, who is the bishop of Rome, is the chief pastor of the church.