The ruined church is composed of two compartments, the eastern one used as a burial enclosure. Built into one of the S nave windows is a reused decorated stone fragment, and in the adjoining churchyard there is a coped, tegulated grave cover. After the Reformation, the barony of Ancrum passed first to the Duke of Richmond and Lennox, and later to the Earl of Roxburgh. Towards the end of the 17thc, the parishes of Longnewton and Ancrum were annexed. At one time there were two villages, Over and Nether Ancrum. Both were burned during the English attacks of 1544-5. The church was rebuilt in 1761-1762 and further work undertaken in 1831-1832. It was finally replaced with a church newly built near the village green in the late 19thc. After this the old church was reduced to form a romantic ruin for William Scott of Ancrum. After the Reformation, the barony of Ancrum passed first to the Duke of Richmond and Lennox, and later to the Earl of Roxburgh.

Located in Teviotdale, the earliest reference to Ancrum comes in the 12thc. In the Inquisitio Davidis (undetaken sometime between 1114 and 1124), Ancrum is listed as ‘Alnecrumba’ in the diocese of Glasgow. The church was an episcopal mensa of the bishop of Glasgow by 1170, when this was confirmed, and it remained part of that see throughout the medieval period. The rectory of Ancrum was a prebend of Glasgow by at least 1275 and mentioned again as such in the 15thc. In 1525, John Doby was referred to as rector. The bishop of Glasgow also had a castle/palace here, where he often resided.

In the past, it was thought that one of the figures on the window stone was an Agnus Dei, but it is actually a Sagitarius-like figure. The animal on the other carved side has a curious upper and lower bulge. Although less prominant, an upper hump can be found on the animals carved on a re-used stone nearby at Knowtownhead, Hassendean. How the Ancrum stone was used originally is intriguing, as each of the two animals stands on the same level and face the same direction, even though they are carved on different sides. When viewed from above, it is clear that the angle at the outward corner is not 90 degrees and the stone is essentially triangular in form, with one corner cut off. This, in conjunction with the outer corner being quite worn, may suggest that this could have been part of a coped grave cover. Animals carved in panels can be found elsewhere in the Scottish Borders, as on a coped grave cover, now under the growth, at Old Cambus. Lang suggested a date in the 11thc for the Old Cambus grave cover, but others have suggested a date in the early 12thc for the carved figures at Ancrum. The tegulated grave cover in the churchyard of the old church at Ancrum has deteriorated in recent years and needs conservation. Comparisons with hogbacks have been made with this type of coped grave cover, with straight top and no beast clasps as ends, and a date later in the 11thc or early 12thc suggested. Originally, the Ancrum one would have looked similar to that, for example, in the churchyard at Lempitaw.