William Ferguson Massey (1856-1925) was a New Zealand political leader and prime minister. His talent for administration saw his country through World War I and led New Zealand to economic recovery.

William Ferguson Massey was born in the village of Limavady a few miles from Londonderry, Ireland, on March 26, 1856. In 1870 he followed his father to New Zealand, where he gained farming experience and by 1890 had set himself up near Auckland as a small farmer. He took to politics as a spokesman for the small farmers and was elected to Parliament in 1894. For 18 years he sat on the opposition benches with the independent Conservatives and was elected opposition leader in September 1903. In February 1909 he announced that his party would thenceforth be known as the Reform party, and in 1912 he emerged from the political confusion to form a government, though lacking a clear majority of seats, and remained in office until his death 13 years later.

During World War I Massey showed his ability in organizing the country for the crisis. In August 1915 he led the Reform party into a coalition with the Liberal party under Sir Joseph Ward, leaving a small Labour minority as the opposition. Both Ward and Massey went to England twice to attend meetings of the imperial War Cabinet, and after the war Massey represented New Zealand at the peace conference.

Massey did not work easily with Ward, who was minister of finance and not inclined to accept a subordinate role, and in 1919 the coalition was dissolved. At the election in December the Reform party won a substantial majority, and Massey was able for the first time to govern without maneuvering among the other parties. He retained his majority in the election of 1922. In 1923 he was able to effect large reductions in income tax and a return to penny postage, but his health was failing, and he died at Wellington on May 10, 1925, just before an election in which his party was to triumph yet again.

Massey was a large man with a homespun appearance and was an effective, if harsh and verbose, speaker. He was devoted to politics and was in some ways stubborn and narrow in outlook, but he gave the impression of sincerity, was respected by his opponents, and was admired for his courage, tenacity, and political acumen.