Trinity, meanwhile, all the younger Fellows had obtained commissions, and the older men naturally wished to do their bit. They therefore deprived me of my lectureship. When the younger men came back at the end of the War I was invited to return, but by this time had no longer any wish to do so.
Source: The Autobiography of Bertrand Russell, v.2 chap. 1:The First War, 1968
More info.:http://russell-j.com/beginner/AB21-250.HTM