Of Etruscan origin - probably named after a temple dedicated to the goddess Isis - Montisi became a Roman outpost and, in the 12th century became the castle of the Cacciaconti family.
Even today, one of the best-known stories of the area concerns Simone Cacciaconti, who, in the 12th century, after dividing the land with his two brothers, tried to impose himself on the village after signs of growing independence on the part of the inhabitants: a bloody battle ensued and, though victorious, Simone plundered the land, killing most of the people.
Upon his death, Cacciaconti, left the lands of Montisi to the Hospital Santa Maria della Scala (St. Mary of the Staircase) of Siena, which, in the 16th century, built a fortified grange for the purpose of storing, guarding and defending the products from the vast territories owned in Val d’Orcia, Crete Senesi and Maremma.
The Grange of Montisi is a fortified structure with an imposing appearance that has undergone numerous additions and renovations in successive eras. Also part of the complex was a tower - a scaled-down copy of the Mangia tower in Siena - destroyed by German troops in 1944.
The Grange today houses one of the smallest theaters in the world.
The main place of worship in the village is the parish church of Santissima Annunziata (Most Holy Annunciation), dating from the 13th century and remodeled several times over the centuries; inside is the altarpiece Madonna with Child between Saints Paul, James, Peter and King Louis by Neroccio di Bartolomeo de' Landi, dating from 1456.
Other churches in the village are the Oratory of Sant'Antonio Abate (St. Anthony the Abbot) - which houses an exhibition of sacred objects - and the Sanctuary of the Madonna delle Nevi (Madonna of the Snows), the patron saint of Montisi, along the road to San Giovanni d’Asso.
