The See or Diocese of Bethlehem was a diocese in the Roman Catholic Church during the Crusades and is now a titular see. It was associated with the Roman Catholic Diocese of Nevers.
In 1099 Bethlehem was captured in the First Crusade. A new monastery and cloister were built by the Augustinians to the north of the Church of the Nativity, with a tower to the south and an episcopal palace to the west. The Orthodox clergy (the Christian presence in the area had until then been Greek Orthodox) were ejected and replaced by Catholic clergy. On his birthday in 1100, Baldwin was crowned King of Jerusalem in Bethlehem — that same year, at Baldwin's request, Pope Paschal II established Bethlehem (never before an episcopal see) as a Catholic bishopric, a suffragan of the Latin Patriarch of Jerusalem. In 1187 Saladin reconquered Bethlehem and the Catholic clergy were forced to let the Greek Orthodox clergy return. Saladin himself in 1192 allowed two Catholic priests and two deacons to return to the diocese, though Bethlehem's economy still suffered from the drastic reduction in pilgrims from Europe.
In 1229 Bethlehem, Jerusalem, Nazareth and Sidon briefly returned to the Kingdom of Jerusalem under a treaty between Frederick II, Holy Roman Emperor and the Ayyubid sultan Al-Kamil, in exchange for a ten-year truce between the Ayyubids and the Crusaders. That treaty expired in 1239 and Bethlehem was then reconquered by the Muslims in 1244. In 1250, with the Mamluks' rise to power, tolerance for Christians in Palestine declined — the Catholic clergy left Bethlehem, whose walls were demolished in 1263. They then returned to Bethlehem in the 14th century and settled in the monastery adjacent to the Church of the Nativity. The Greek Orthodox in the meantime took over control of the Church of the Nativity and shared control of the Milk Grotto with the Catholics and the Armenians.