[2] A church at Fleet is known to have existed as early as 1086 when one was recorded in the Domesday Book, with a monk from Abbotsbury Abbey named Bolla as the village's priest.

The church was dedicated to Holy Trinity and belonged to the Christchurch Priory until the Dissolution of the Monasteries.

[4] The church's nave was significantly damaged in the Great Storm of 1824,[2] which also destroyed a number of the village's houses.

[5] With the construction of the new church, the nave of the original was demolished in 1827, but the chancel was retained and repaired for use as a mortuary chapel.

[7][8] The surviving chancel is built of local rubble, with freestone dressings and stone slate roofs.