There have been two monastic foundations at Hackness, first an Anglo-Saxon nunnery founded in 680 and second a cell of Whitby Abbey that was used as a refuge when pirates forced the monks away from the coast.
The original establishment was a nunnery founded by St. Hilda of Whitby in 680, the year of her death. According to legend the bells of Hackness tolled at the moment St. Hilda died fourteen miles away in Whitby. This was probably a Celtic style of nunnery, with the cells housed in small individual buildings, as at Whitby, although there is some evidence of a common dormitory. Very little has survived from this early period, but there are fragments of an 8th or 9th century cross in the church of St. Peter. We don't know when this nunnery was disappeared, but it is possible that it was destroyed by Danes in 867, in a period when several other Anglo-Saxon monastic establishments in the North York Moors also disappear.
The second monastic establishment was tied to the re-foundation of Whitby Abbey (before 1078). In around 1078 the monks of Whitby were forced to abandon their coastal location by pirate raids, and appear to have split. One party, under Stephen of Whitby, founded a new monastery at Lastingham before moving to York. The second, under Prior Serlo de Percy, moved to Hackness.
William de Percy, the founder of Whitby Abbey, granted the monks his part of the manor Hackness, including the churches of St. Mary and of St. Peter. St. Marys became the parish church while St. Peters was the monastic church. According to a Whitby charter this was 'where out monks serve God, die and are buried'. Prior Reinfrid, the first prior of the restored abbey was buried at Hackness, suggesting that it was seen as part of the home church. The establishment at Hackness wasn't a distinct monastic cell and was instead run as part of the main Abbey, with a small number of monks living at the second site. There are said to have been four monks living at Hackness at the dissolution of the monasteries.
Grid Reference: NY 969 905