The Parish Church of St Helier is the parish church of the parish of Saint Helier, Jersey. It is a Church of England church, one of the twelve 'Ancient Parish Churches' of Jersey, and serves as the Island's civic church and Pro-Cathedral.
Helier was a Belgian saint who lived as a hermit for some ten years on an islet in St Aubin's Bay, about three-quarters of a mile off the south coast of Jersey. In AD 555 he was martyred by Saxon pirates, beheaded by their leader who feared his men would be converted by Helier's preaching. In consequence Helier soon came to be venerated by the Islanders, and eventually was adopted as the Patron Saint of both Jersey and its capital.
Although the church is some way inland today, this is a result of land reclamation, and it once lay on the shore – indeed, the church used to have iron rings set into the wall to tie up boats. The site of the church would have been the closest accessible location on dry land to the site of Helier's martyrdom. It is believed that a chapel was erected on the site of the present building very shortly after Helier's death, but the present church was begun in the 11th century. The earliest record is in a document regarding the payment of tithes signed by Duke William II of Normandy, which – because William signed himself Duke rather than King – is assumed to pre-date the Norman Conquest of 1066. All that is visible of the 11th century structure are the remains of window arches on either side of the Choir. The building was reconsecrated in 1341 for unknown reasons.
The church building was extended to roughly its present size by the end of the 12th century, but most of that building is also lost. The sections of wall flanking the East Window, part of a pier on the north east side of the crossing, the west face of the North Door and the adjoining section to the west, and a small section of wall opposite are all that remain of the building period of roughly 1175 to 1200. The porch attached to the North Door and the greater part of the nave and crossing were built in the second quarter of the 15th century. The date of the chancel is now more or less impossible to determine, since the original walls have been obliterated by the North Chapel on the one side (built in the last quarter of the 13th century, originally the Mortuary Chapel) and the South Chapel (last quarter of the 15th century, commonly but erroneously known as the Lady Chapel) on the other. Most of the North transept dates to the second quarter of the 13th century. The present South transept, vestry, and the westwards extension to the nave (now converted into a narthex) all post-date c. 1820, and are largely Victorian. A major renovation and re-ordering of the church began in 2007, and will take several years.