In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described St Osyth like this:
OSYTH (St.), a village, a parish, and a sub-district, in Tendring district, Essex. The village stands on acreek of the river Colne, 1¾ mile N of the coast, 2¾ S E of Brightlingsea r. station, and 11 S E of Colchester; is one of the oldest places in the county; was known to the Saxons as Chich; took its present name from St Osyth.daughter of King Redwald and wife of King Sighere of the East Saxons; and has a post-office‡ under Colchester, and a fair on Holy Thursday. ...
The parish contains also the hamlets of New Frowick and Wigborough-Wick; extends to the coast; and comprises 8, 571 acres of land, and 1, 100 of water. Real property, £13,070. Pop., 1, 638. Houses, 349. The manor, with Hill House, belongs to Brandreth, Esq. A nunnery was founded here by St. Osyth, who was its first abbess, and suffered martyrdom by the Danes. The nunnery was burnt by the Danes; and the remains of it were given, by Canute, to Earl Godwin. An Augustinian priory was founded on its site, in 1118, by Bishop Belmeis; and passed to the Cromwells, the D' Arcies, and the Earls of Rochford; and considerable portions of it are now included in the mansion called the Priory, the residence of J. H. Johnson, Esq. Much of the land is marsh; but part is comparatively high, and includes Beacon Hill. A battery and two martello towers are on the coast. The living is a p. curacy in the diocese of Rochester. Value, £150. Patron, the Bishop of Rochester. The church is ancient, large, and good; has aisles and a tower; and contains some monuments of the D' Arcies. There are chapels for Wesleyans and Swedenborgians, a national school, and charities £10.The sub-district contains also seven other parishes. Acres, 26, 942. Pop., 6,072. Houses, 1, 351.
GB Historical GIS / University of Portsmouth, History of St Osyth, in Tendring and Essex | Map and description, A Vision of Britain through Time.
Date accessed: 28th March 2017
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