As heir apparent to the Earldom of Athlone, he was known as Lord Trematon, but he died before he could inherit the title.

His parents were Prince Alexander of Teck and the former Princess Alice of Albany, great-grandson and granddaughter of George III and Queen Victoria respectively.

[4] During the First World War, anti-German feeling in the United Kingdom led Rupert's uncle King George V to renounce all Germanic titles for himself and his family.

Viscount Trematon died on 15 April 1928 from an intracerebral hemorrhage as a result of a car crash in France.

[4] 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.