The Collegiate Church of St Peter at Westminster is a large Gothic abbey church in the City of Westminster, London, England, situated to the west of the Palace of Westminster. It was a Benedictine monastic church until the monastery was dissolved in 1539. Between 1540 and 1556, the “abbey” was referred to a “cathedral.” However, since 1560, the building is no longer an abbey or a cathedral, instead, Westminster Abbey, as it is so called today, holds the status of a Church of England “Royal Peculiar,” an honor bestowed upon the site by Elizabeth I, meaning a church directly responsible to the sovereign. [A “peculiar” is applied to those ecclesiastical districts, parishes, chapels or churches that are outside the jurisdiction of the bishop and archdeacon of the diocese in which they are situated.] Beginning in 1066, with the coronation of William the Conqueror, all coronations of English and British monarchs have been held at Westminster Abbey. Since 1100, there have also been 16 royal weddings conducted within its walls.

https://en.wikipedia.org/wiki/Westminster_Abbey#/media/File:Westminster-Abbey.JPG

According to a tradition first reported by Sulcard in 1080, a church was founded at the site, known as Thorn Ey, in the 7th century, when Mellitus was a Bishop of London. King Henry III gave the orders for the construction of the present church. The recorded origins of the Abbey date to the 960s or early 970s, when Saint Dunstan, Bishop of London and later Archbishop of Canterbury, and King Edgar of England installed a community of Benedictine monks on the site.

One of the legends of the church has to do with its origin. It stands on Thorn Ey, or Thorn Island. The “island” is about two miles to the west of the old Roman city of London. It is where two branches of the River Tyburn come together. Some believe, pagan King Saberht  (c. 604 – c. 616) of the East Saxons found religion and had a hand in the building of a episcopal church in London. In 604, the Gaulish churchman Mellitus was consecrated by Augustine as bishop in the province of the East Saxons, which had a capital at London, making him the first Bishop of London. Bede tells that Sæberht converted to Christianity in 604 and was baptised by Mellitus, while his sons remained pagan. Sæberht then allowed the bishopric to be established. (Saberht of Essex)

Floor Plan 1894 ~ Public Domain https://en.wikipedia.org/wiki/Westminster_Abbey#/media/File:London_westminster_1894.jpg

A long-standing tradition says that “St Peter appeared to a young fisherman and demanded that a church dedicated to him be constructed on Thorney Island – and it was. Another story had St Peter appearing to Mellitus on the day when Sebert’s church was consecrated and conducting the ceremony himself. In later centuries, Thames fishermen regularly gave gifts of salmon to the abbey on St Peter’s Day, June 29th, and the Fishmongers’ Company still presents a salmon to Westminster Abbey every year.” (History.com) 

When Edward the Confessor was crowned King of England in 1042, a Benedictine community resided upon Thorny Island. After 1013, Edward had spent much of his early days in Normandy because England had been taken over by the Danes under Sweyn Forkbeard and then Cnut. Invited back by the last Danish king, who was his half-brother, Edward succeeded peacefully to the English throne in 1042.

Edward the Confessor overseeing the building of Westminster Abbey ~ https://www.historytoday.com/richard-cavendish/consecration-westminster-abbey

While in Normandy, Edward had made a vow to go on pilgrimage to St Peter’s in Rome to give thanks for his restoration to the English throne, but was released by his vow by Pope Leo IX on condition that Edward build or restore a monastery and dedicate it to St Peter. Edward was a deeply pious man and he accepted the obligation with exemplary thoroughness. He chose the Benedictine monastery on Thorney Island and to make sure things were done properly he installed himself in a palace close to the abbey, between the river bank and what is now the street called Whitehall. The monks and lay brothers had diligently cleared Thorney Island of its thorns and made it a more habitable place. Edward now appointed a new abbot, brought in more monks and decided to build a far grander abbey church in the Norman style of the day. It was there that he intended to be buried.

The church was formally consecrated on 28 December 1065. Edward did not live to enjoy the fruits of his efforts. He died on 5 January 1066. Even so, he was buried in front of the high altar. After the Battle of Hastings, William the Conqueror had himself crowned and anointed King of England, the ceremony taking place on Christmas Day 1066 in Westminster Abbey, as a symbol to all that he was Edward the Confessor’s legitimate successor. 

“Edward the Confessor was canonised as a saint in 1161. In 1245 his fervent admirer, Henry III, began a massive programme of rebuilding and enlarging the Confessor’s church. He spent a fortune on it and it was Henry who gave Westminster Abbey its lasting architectural character. In 1269 he helped to carry the Confessor’s remains to a special chapel behind the high altar where they have remained through all the centuries since. When he died in 1272, Henry was buried in St Edward’s chapel.” (The Consecration of Westminster Abbey)