St Osyth, according to legend, founded a nunnery at Cicc (later to be named St Osyth in her honour) in the seventh century. Only a few Saxon finds have been recovered from the town, but these do indicate activity during the eighth to the tenth centuries, and the Domesday Book (Rumble, 1983) shows that the area supported quite a thriving community in the first half of the eleventh century.
The most important feature of medieval St Osyth is the Priory, which was founded before 1127 (possibly in 1121), for the Austin Canons, by the Bishop of London The priory became an Augustinian Abbey in about 1200 AD. The buildings are characterised by magnificent chequer-board patterning of ashlar, septaria and flint. The town of St Osyth is thought to have been founded by the priory, the main settlement area is centred on the cross-roads formed by the road that runs from Clacton to the creek and the Colchester road, with a second focus 600m to the west beside the creek, where there is a quay. There is an undated medieval charter which records the granting of a fair and a market to the Abbey.
The most dramatic change in the post-medieval period was the suppression of the priory in 1539. In 1553 it came into the possession of Lord Darcy who converted some of the buildings into a house and levelled others, including the abbey church. About 1600 a large red brick built house was erected on the site of the northern portion of the cloister. The priory grounds were landscaped in the eighteenth century. The town itself appears to have changed little in the post-medieval period, with expansion only taking place in the twentieth century.
The economy of medieval St Osyth appears to have centred on the priory and on the town’s function as a market-centre for the eastern end of the Tendring peninsula. Oyster fishing also formed an important part of the local economy. In the post-medieval period the Lord Darcy’s House took over the role of the priory as the main patron of the town, whilst the market function and the oyster-fishing continued. A tidal corn-mill was built in the post-medieval period on a causeway across the creek.