Rupert Cambridge, Viscount Trematon

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.

Prince Rupert was a haemophiliac, a condition he inherited through his mother from his great-grandmother, Queen Victoria, through his grandfather, the Duke of Albany (himself a haemophiliac).

He was educated at Trinity College, Cambridge.

During World War I, anti-German feeling in the United Kingdom led Rupert's uncle King George V to change the name of the Royal House from the German House of Saxe-Coburg-Gotha to the more English-sounding House of Windsor. The King also renounced all his Germanic titles for himself and all members of the British Royal Family who were British citizens, including Rupert.

In response to this, Prince Alexander, Rupert's father, renounced his title of a Prince of Teck in the Kingdom of Württemberg and the style His Serene Highness. Alexander, along with his brother, Prince Adolphus of Teck, adopted the name Cambridge, after their maternal grandfather, Prince Adolphus, Duke of Cambridge.

A few days later, the King created his brother-in-law Earl of Athlone and Viscount Trematon. Alexander was now styled The Right Honourable The Earl of Athlone. Rupert adopted the courtesy title of Viscount Trematon. His mother retained her title of Princess of Great Britain and Ireland with the style Her Royal Highness and became known as Princess Alice, Countess of Athlone.

Rupert died on 15 April 1928 from an intracerebral hemorrhage as a result of a car crash in France. On 1 April 1928 Trematon was driving with two friends on the road from Paris to Lyon. While overtaking another car, Trematon's car hit a tree and overturned. One of his friends died from injuries and Trematon was taken to a nearby hospital at Belleville-sur-Saône with a slight fracture of the skull. He never recovered and died in hospital in the early hours of 15 April. His funeral took place in St George's Chapel, Windsor Castle, and was attended by King George V and Queen Mary. He was buried in the Royal Burial Ground, Frogmore, on 20 April 1928. His death, following the death of his baby brother Maurice in 1910, meant that the title of Earl of Athlone became extinct in 1957 when his father died.

• His Serene Highness Prince Rupert of Teck (1907–1917)
• Mr. Rupert Cambridge (1917)
• Viscount Trematon (1917–1928)