Alternative successions of the English crown

The succession to the Crown of the United Kingdom is determined by the Act of Settlement 1701. This Act provided that, should William III and Anne both die without issue, the Crown would be settled on Sophia of Hanover (a granddaughter of King James VI and I) and her Protestant heirs. At the time the Act was passed, it was highly likely that both William and Anne would die without issue, and this indeed proved to be the case. This law has applied ever since, except for an amendment passed in 1936 that any descendants of Edward VIII would have no claim whatsoever to the Crown. This amendment proved academic, as the abdicated King Edward VIII died without issue in 1972.

Concomitantly, British history provides several opportunities for alternative claimants to the Crown to arise, and historical scholars have on occasion traced to present times the heirs of those alternative claims.

Throughout this article, the names of the historical monarchs appear in bold and the names of "would-have-been" monarchs are in italics.

Richard II abdicated in favour of Henry Bolingbroke on 29 September 1399. However, Henry was not next in the line to the throne; the heir presumptive was Edmund Mortimer, Earl of March, who descended from Edward III's second surviving son, Lionel of Antwerp, whereas Henry's father, John of Gaunt, was Edward's third surviving son.

Had Edmund inherited instead, the alternative succession would have been short-lived, for it re-united with the historical crown when Edward IV was declared king in 1461.

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