List of monarchs in Britain by length of reign

The following is a list, ordered by length of reign, of the monarchs of the United Kingdom of Great Britain and Northern Ireland (1927–present), the United Kingdom of Great Britain and Ireland (1801–1927), the Kingdom of Great Britain (1707–1801), the Kingdom of England (871–1707), the Kingdom of Scotland (878–1707), the Kingdom of Ireland (1542–1800), and the Principality of Wales (1216–1542).

Queen Elizabeth II became the longest-reigning British monarch on 9 September 2015 when she surpassed the reign of her great-great-grandmother Victoria. On 6 February 2017 she became the first British monarch to celebrate a sapphire jubilee, commemorating 65 years on the throne.

These are the ten longest reigning monarchs in Britain for whom there is reliable recorded evidence.

The longest claim by a pretender was that of James Francis Edward Stuart (the "Old Pretender"), who was the Jacobite pretender to the thrones of England, Scotland and Ireland for 64 years, 3 months, and 16 days (17 September 1701 – 1 January 1766).

1 - Elizabeth II

2 - Victoria

3 - George III

4 - James VI and I

5 - Henry III

6 - Edward III

7 - William I

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