The Abbey of Monte Oliveto Maggiore is a large Benedictine monastery in the Italian region of Tuscany, 10 km south of Asciano. Its buildings, which are mostly of red brick, are conspicuous against the grey clayey and sandy soil.
It is a territorial abbey whose abbot functions as the bishop of the land within the abbey's possession, even though he is not consecrated as a bishop.
It is the mother-house of the Olivetans and the monastery later took the name of Monte Oliveto Maggiore ("the greater") to distinguish it from successive foundations at Florence, San Gimignano, Naples and elsewhere.
It was founded in 1313 by Bernardo Tolomei, a jurist from a prominent aristocratic family of Siena. In 1319 or 1320 it was approved by Bishop Guido Tarlati as Monte Oliveto, with reference to the Mount of Olives and in honour of Christ’s Passion. The monastery was begun in 1320, the new congregation being approved by Pope Clement VI in 1344. The abbey was for centuries one of the main land possessors in the Siena region. On January 18, 1765, the monastery was made the seat of the Territorial Abbacy of Monte Oliveto Maggiore.