Final answer:
Hugh Gaitskell was challenged for the leadership of the Labour Party in 1960 by Harold Wilson, who was unsuccessful in this attempt.
Step-by-step explanation:
Hugh Gaitskell was challenged for the leadership of the Labour Party in 1960 by Harold Wilson. The challenge was unsuccessful, and Gaitskell retained his position as party leader until his death in 1963. The leadership contests within the Labour Party have been significant in shaping the party's direction and policies, and the 1960 challenge by Wilson marked an important event in the party's history.