Rupert Philip Lonsdale (5 May 1905 – 25 April 1999) was a British submarine commander, prisoner of war and Anglican clergyman.

He was forced to surrender his boat in World War II after he had succeeded in rescuing her and her crew from the sea bed after she struck a mine.

Lonsdale was born in Dublin and educated at St. Cyprian's School, Eastbourne and the Royal Naval College, Osborne.

But he failed to persuade Admiral Max Horton to reconsider his orders, and Seal sailed from Immingham on 29 April 1940.

[1] Once on the surface, Lonsdale tried to make for the nearby Swedish coast and the crew destroyed the secret Asdic equipment and confidential papers.

Despite a hard winter, enforced idleness, and the unnatural life led by any prisoner they all look fit; I cannot emphasis this too much; they really do look well, which is great credit to them and I would be grateful if you could let their next of kin know as you kindly did before."

His last command was the new Algerine-class minesweeper Pyrrhus, which he brought up from Glanton before joining an operational flotilla at Portsmouth in January 1946.

His first curacy was with a mission church at Rowner, near HMS Dolphin, the submarine base at Gosport, followed by becoming vicar of Morden-with-Almer in Dorset in 1951.

Lonsdale retired to Hampshire, but held several part-time chaplaincies for the Anglican Church's European diocese based on Gibraltar.

This led to a three-year stay in Tenerife (1970–73) before he returned to England for some time in the clergy hospice at College of St Mark at Audley End.

[7] He was survived also by his son John Lonsdale, Fellow of Trinity College, Cambridge, a historian of East Africa.

He agreed, provided that he could write a foreword making it clear that he was a reluctant contributor, who trusted that it might help some readers to find faith in God.

The book includes a tribute from him to his ship's company and the authors prefaced his foreword with the first seven verses of Psalm XLVI from which they drew their title.