Wainfleet St Mary Is a village to the S of the port and market town of Waiinfleet All Saints are a in the East Lindsey district of Lincolnshire. It is on the A52, 5 miles SW of Skegness and 14 miles NE of Boston. St Mary's is a large marshland church primarily of the Early English and Perpendicular periods with a W tower, five-bay N aisle, four-bay S aisle, and short chancel. The S aisle and S porch were restored in 1874-5, the chancel in 1880-1, and the N aisle and nave roof rebuilt in 1892. The W tower arch leading into the nave has Romanesque respond capitals.

Wainfleet All Saints and Wainfleet St Mary's are treated as a single entity in the Domesday Survey, In order of size, a large holding of 20 carucates and 2 bovates that included land in Haugh and Calceby and Theddlethorpe and Mablethorpe as well as Wainfleet was held as sokeland of Earl Hugh's manor of Greetman. 7½ bovates were held by 3 brother sin 1066 and by Bondi and Ralph from the Bishop of Durham in 1086; 2½ bovates were held by Eudo FitzSpirewic as a berewick of Keal, and 1 bovate as a separate holding; and finally 2 bovates were held by Gilbert de Ghent as a berewick of his manor of Croft. There was a church here by 1180. In that year Simon of Wainfleet and his son Guy gave the church of St. Mary of Wainfleet to the abbey of Bury St. Edmunds. However, the Cistercian nuns of Stixwould Priory contested this, laying claim to the parish church themselves. In 1184 Geoffrey, bishop of Ely, and Robert, prior of Merton, settled the claim in favour of Stixwould.