Watlington sits just to the N of the Chiltern hills and the historic Icknield Way, in the SE of the county of Oxfordshire. The church of St Leonard is located at the edge of the village, NW of the high street. Its peripheral location is perhaps explained by being next to the site of the 'castle'; the location of the Crown manor. The present building mainly dates to the 14thc, but some 12th-c features survive. The church consists of a four-bay nave, a S aisle, a chancel and a S chapel in flint rubble with limestone ashlar quoins, dressings and bands. The limestone ashlar tower at the W end dates to the 15thc. Much of the rest of the church was rebuilt by H. J. Tollit and E. Dolby in 1877 in the Decorated style. The N aisle (added in 1877) is of coursed and dressed limestone rubble. The tile roof was restored in the 19thc and features decorative ridge tiles. The NW extension for a kitchen and toilets in knapped flintwork with ashlar quoins has been done in recent years.

Fragments of Romanesque sculpture are reset in the S aisle, in the chancel, in the organ chamber and in the vestry: they consist of two capitals, a colonette, a sculpted block, two carved heads and a tympanum.

Watlington is first mentioned in a charter (Sawyer S217) dated to 880-7 containing a grant by Æthelred, dux et patricius of Mercia, to the bishopric of Worcester of 6 hides (mansiones) at Brightwell Baldwin and 8 at Watlington to pertain to the church at Readanoran (i.e. Pyrton, Oxon).

Domesday Book reports that in 1066 'Watelintone' was held by Alfhelm; in 1086 it was a possession of Préaux Abbey (Normandy).

In 1068 the estate, later known as 'Watlington manor', was held for 8 hides by Robert D'Oilly, Constable of Oxford castle. Watlington was later held as a fee of the Honour of Wallingford and in 1297 was regarded as being in the bailiwick of the Honour. In 1129 Robert included the advowson of Watlington among the foundation properties of Oseney Abbey, and his grant was confirmed by Henry I between 1129 and 1133. The D'Oilly family supported the Empress Maud in the civil wars of Stephen's reign and seems to have lost Watlington after the rout of Winchester in 1141. King Stephen gave the estate to Halinad de Bidun, a Norfolk baron and one of the knights of Hugh Bigod, Earl of Norfolk, who had changed his allegiance to Stephen. Bidun granted the advowson and part of his demesne land to Oseney between about 1154 and 1162. The D'Oilly family, however, had not relinquished its claim and Oseney was careful to get confirmation of its rights in Watlington from all parties concerned.

Henry III, despite the claims of D'Oilly and others, had granted a lease of Watlington in 1229 to Richard, Earl of Cornwall. A park, the later Watlington Park, was made before 1272 by Richard, Earl of Cornwall.

Oseney had evidently appropriated the church by 1185 at least, and early in the 13thc a vicarage was ordained. The church remained in Oseney's possession until its dissolution in 1539, although it sold the presentations of 1502 and 1538.

The church is interesting for the early material reset as display items after the rebuilding by Tollit and Dolby in 1877. Of these the reset doorway and capitals belong to the c.1100, while the corbel heads are rather later - Sherwood and Pevsner suggest that the one in the chancel is probably 13thc.