The parish of Lassington lies north and east of Highnam and is bounded on the north and east by the River Leadon. The manor of Lassington, as listed in the 1086 Domeday Book, belonged to the Archbishop of York.
The earliest feature is the Tower of St. Oswald’s church, which is all that remains of what is believed to be a Saxon church. The earliest known reference to a church is its re-dedication to St. Oswald in1095 after the building of the Norman nave, chancel and side-chapel.
In common with many churches in the area, there is an associated Lassington Court. The manor house was probably on the site of the Lassington Court farmhouse, with a priest’s house adjacent to present day Astman’s Farm.