Short answers, pulled from the story.
The first recorded use of the term Catholic Church appears in a letter written around the year 100 by Ignatius of Antioch to the Smyrnaeans. This letter declared that where the bishop appears, there is the universal church. The term was derived from the Greek word katholike meaning universal to distinguish this community from other groups.
The Catholic Church teaches that it was founded by Jesus Christ who gave the Great Commission to his apostles. The Church considers itself the one true church with bishops serving as the successors of the apostles and the pope as the successor of Saint Peter. This belief in apostolic succession forms the backbone of its authority.
The Catholic Church became the state church of the Roman Empire in 380 through the Edict of Thessalonica issued by Emperor Theodosius I. This edict established Nicene Christianity as the state church and continued within the Byzantine Empire until its fall in 1453. The Edict of Milan in 313 had previously legalized the Christian faith under Constantine the Great.
The Catholic Church encompasses an estimated 1.41 billion baptized members as of 2025. According to the Annuario Pontificio, church membership was 1.406 billion at the end of 2023 representing 17.4% of the world population. Catholics represent about half of all Christians globally.
The Great Schism between the Catholic Church and the Eastern Orthodox Church was symbolically marked by mutual excommunications in 1054. The definitive rupture was the result of a long process including the Fourth Crusade and the sacking of Constantinople. The Council of Chalcedon in 451 had previously elevated the see of Constantinople creating tensions that eventually led to the schism.
Pope Leo XIV was elected as Pope in the 2025 conclave following the death of Pope Francis. He is the first Augustinian pope, the first North American pope, born in Chicago in the United States, and the first pope of Peruvian citizenship. Pope Francis served until his death in 2025 after which Leo XIV was elected.