Gaitskell had lost the 1959 general election and had seen the Labour Party conference adopt a policy of unilateral nuclear disarmament which he considered disastrous and refused to support.

[1] However his move provoked firm opposition from the major unions and the left-wing of the party, and facing certain defeat, he withdrew it in March 1960.

[2] In the meantime the Government's decision to abandon the British Blue Streak missile and buy instead the US Skybolt system had made nuclear weapons a prominent political issue.

[5] One left candidate who was keen to fight for the deputy leadership was Harold Wilson, who found himself subjected to pressure to challenge Gaitskell instead.

[6] Wilson resisted but his hand was forced when Anthony Greenwood resigned from the Shadow Cabinet saying he would not serve under Gaitskell while he defied conference decisions.