Churchill Rose to power in May 1940 and Chamberlain died of cancer in November 1940 at 71 years of age. So Chamberlain lived for less than six months after stepping down as PM. For much of this time, he was not in good health and experiencing significant pain.

During those six months Chamberlain helped keep the Conservative party in line behind Churchill, who was PM of a unity government - a coalition of all the major parties. Formally Chamberlain held the offices of Lord President of the Council, War Cabinet member, and Leader of the Conservative party. When he died, Churchill said of him "Whatever shall I do without poor Neville? I was relying on him to look after the Home Front for me."