Prince Rupert of Teck (Rupert Alexander George Cambridge; 24 August 1907 – 15 April 1928) was a member of the British Royal Family, a great grandson of Queen Victoria. During World War I, the British Royal Family relinquished their Germanic titles, and Prince Rupert assumed the style Viscount Trematon in 1917.

Prince Rupert was born on 24 August 1907 at Claremont House, Esher, Surrey, England. His father was Prince Alexander of Teck, the fourth and youngest child, and third son, of Prince Francis, Duke of Teck, and Princess Mary Adelaide of Cambridge. His mother was Princess Alexander of Teck (née Princess Alice of Albany), the daughter of Prince Leopold, Duke of Albany (youngest son of Queen Victoria), and Princess Helena of Waldeck and Pyrmont. They were second cousins once removed: Victoria and Mary Adelaide being male-line granddaughters of George III. Rupert took his original title of Prince of Teck and style, His Serene Highness, from his father; during his childhood being referred to as Prince Rupert of Teck.

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