Born in Wallasey, Cheshire, the son of a John Hinkes Tilman (wealthy sugar merchant) and his wife Adeline.
Educated at Berkhamsted Boys school.
First World War - commissioned as a second lieutenant in the Royal Field Artillery. He fought at the Battle of the Somme, and was twice awarded the Military Cross for bravery.
Known for climbing with Eric Shipton in Kenya and East Africa including Kilimanjaro.
Involved in two of the 1930s Mount Everest expeditions - participating in the 1935 Reconnaissance Expedition, and reaching 27,200 feet without oxygen as the expedition leader in 1938.
1936 - lead an Anglo-American expedition to Nanda Devi. Tilman and Noel Odell succeeded in making the first ascent of the 25,643 ft mountain, which remained the highest summit climbed by man until 1950.
1939 - was the first man to attempt climbing in the remote and unexplored Assam Himalaya.
1947 - he attempted Rakaposhi, then made his way to Kashgar to join up with Eric Shipton to make an attempt on Muztagh Ata which nearly succeeded.
He was awarded in 1952 the Royal Geographical Society's Founder's Medal for his achievements.
Second World War - he volunteered for service seeing action during the Battle of France helping to cover the retreat in Flanders before getting to the beaches at Dunkirk. He then served in North Africa, Iraq and Iran before being called on for special duty in 1943. He was dropped by parachute into Albania behind enemy lines to fight with Albanian and Italian partisans. For his actions there he was awarded the Distinguished Service Order and was given the keys to the city of Belluno which he had helped save from occupation and destruction.
Following the War he took up deep sea sailing. On his last voyage in 1977 (aged 80) he travelled with mountaineers to the South Atlantic to climb Smith Island. En route to the Falkland Islands the crew disappeared and it was presumed the ship sunk.