Rupert's health began to decline in his later years, possibly due to the cumulative effects of his active life and various injuries sustained in battle.

Rupert died in his residence at Spring Gardens, London. The cause of death was reported to be pleurisy. His death marked the end of a remarkable and multifaceted life.

Rupert was buried in Westminster Abbey, a testament to his prominent role in English history and his service to the Crown.

Rupert's legacy has endured through the centuries, remembered as a courageous military commander, a skilled naval tactician, a scientist, an artist, and a colonial entrepreneur. He remains a fascinating and complex figure in European history.