Henry was a son of David Mitchell (1844-1912) & Elspet Esplin (1845-1924) Horne. He arrived on the 'City of Auckland' with his parents when he was 5.
He was first elected to the Woodville Borough Council in the year 1903, and was re-elected in 1905. He was born in Forfarshire, Scotland, in January, 1873, and is the second son of Mr. D. M. Horne, of Woodville.
written about 1908 .. He came to New Zealand with his parents at five years of age and was educated at the Waipukurau and Woodville public schools. He afterwards decided to follow the trade of a coach builder,and was then apprenticed to the trade at Palmerston North. Four years later he entered his father's employment as manager of the coach-building department of the latter's Woodville business. In 1901 Mr. Horne became a partner in the firm of Horne and Riley, which took over the business on the retirement of his father.
. partners with John Campbell Riley (1851-1905)
In 1903 he became sole proprietor, and has since conducted a steady and prosperous business, including a branch business at Ballance. Mr. Horne was for twelve years a member of the Woodville Fire Brigade, of which he was secretary for nine years; has been a member since its formation of the local volunteer corps, of which he is senior lieutenant; is a member of the committee of the Presbyterian Church, a member of the Horticultural Society, a P.C.R. and Treasurer of the Rechabite Lodge, and a trustee and senior warden of the local Lodge of Freemasons.

Henry was the 11th Mayor of Woodville 1914-1931 & 1935-1938
He married Elizabeth Thomas (1879-1922) in 1899
they had a son
1900 - 1966 John Thomas Horne
He remarried in Woodville in 1929 to Ethel Constance Nelson (1894-1990). She died in Napier and was cremated at Hastings.

In May 1937 he was 1 of 2 Woodville recipients of the Coronation Medal in recognition of their services .. Mr Henry Palmer Horne, who has been and still is, one of Woodville's leading men, having carried out the Mayoral duties for just over 19 years and Mrs Mary Frances Susan McConnon, is the other, who has taken an active part in the district, being an energetic support of the New Zealand Labour Party and secretary of the local branch.