jubilee (jōˈbĭlē) [key], in the Bible, a year when alienated property and land were restored, slaves were manumitted, debts were forgiven, and a general sabbatical year was observed in agriculture. It occurred once every 50 years, at the end of a series of seven sabbatical years as prescribed by the Book of Leviticus. In the Roman Catholic Church, the name is applied to a holy year when special privileges are given for the pilgrimage to Rome. The first holy year was celebrated in 1300. The pope proclaimed (1343) that holy years would recur at 50-year intervals; in 1470, the interval was reduced to 25 years. Extraordinary jubilees celebrated the 50th anniversary of Pope Pius XI's ordination (1929) and the conclusion of the Second Vatican Council (1966).