He was born in Bibbenluke to pioneer William John Horne and Anne Louise Wilson.
He taught at Coolah Bridge from 1890 to 1899, when he resigned to farm a property at Leadville.
He was elected to the New South Wales Legislative Assembly in 1907 as the Labor member for Liverpool Plains.
His resignation, together with that of Mudgee MLA Bill Dunn, left the McGowen government without a majority, forcing the adjournment of parliament.
Horne did not contest the resulting by-election, which was won by the Liberal candidate, but unlike Dunn he did not return to the Labor Party and in 1917 was appointed to the Legislative Council as a Nationalist.