William Henry Walker (January 1842 in Castlecomer, County Kilkenny, Ireland - May 15, 1916 in Manhattan, New York City) was an American politician in New York. He emigrated to the United States and settled in New York City. He started as a carpenter - cabinetmaker and became a contractor, builder, and owner of a lumberyard; and entered politics as a Democrat. He married Ellen Ida Roon (Oct 1857 - Aug 19, 1917), daughter of an Irish American New York politician, James E. Roon (1828 - Dec 7, 1890). He was a member of the Board of Aldermen from 1887 to 1890; and a member of the New York State Assembly in 1892 (New York Co., 9th D.) and 1893 (New York Co., 8th D.).