Complex sentence: In 1936, Hart was offered a position with the then Imperial War Graves Commission which he accepted, a role which involved overseeing the cemeteries and memorials established by the Commission in the Middle East.
Split into simpler sentences: In 1936, Hart was offered a position with the then Imperial War Graves Commission which he accepted. The role involved overseeing the cemeteries and memorials established by the Commission in the Middle East.