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In page Henry Brooke, Baron Brooke of Cumnor:

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Brooke was born in Oxford,[1] the son of artist Leonard Leslie Brooke and his cousin Sybil Diana Brooke.[2] He was educated at Marlborough College, where he was a classmate of Rab Butler, and Balliol College, Oxford. He had an elder brother, 2nd Lt. Leonard Stopford Brooke, who was killed in Germany in 1918 while serving with the Army Cyclist Corps.[3][2]