King Zvonimir in the year 1078 granted an estate in the Field of Kaštela to the convent of Benedictine nuns. A pre-Romanic church of St. Kuzma and Damjan was built there in the 12th century, over remains of an ancient necropolis and an early-Christian church (findings of early-Christian sarcophagi). The relics of St. Virgin Mary, St. Kuzma and Damjan, and the king Stephen of Hungay are kept there near a Roman villa rustica. An oak, over 700 years old, stands in front of the church, under which, according to the legend, Croatian king Zvonimir rested there once.
In 1545 Benedictine nuns completed building of Kaštilac on a reef called Gomilica. The entrance was protected by high keep and a drawbridge. A few families from a ravaged settlement Kozice lived also in the fortress. The other residents built their houses near by the sea.
The old parish church from the 18th century is noted for its carved Baroque doors.
Fulgencije Bakotić, a wood carver and a priest was born in Kaštel Gomilica in the 18th century. He was well-known for his crucifixes. One of them is in the parish church, two in the Poljud monastery, one in the Museum of the Town of Kaštela and a few in Italian monasteries.