William Wirt Witmer grew up the 12th of 13 children on Pennsylvania farm. He attended school at Gettysburg College, leaving it to enlist in the 104th Pennsylvania Volunteer Infantry. After being mustered out he studied law and came to Muscatine, Iowa, to start his practice, but became interested in newspaper work. He and Mary C. Stein were married in Philadelphia in 1871 and soon after decided to settle in Des Moines. They had four children. Helen and Mabel survived to adulthood. Mabel married Jay E. Tone, Sr, son of Isaac Tone, cofounder of Tone Bros. spices, at the family home. Helen married Gerard S. Nollen.
Witmer founded the Evening Leader and went on to help organize the Western Newspaper Union, a newspaper syndicate. He was one of many movers and shakers that discussed building a coal palace as a tourist attraction in Des Moines. It never panned out, but Ottumwa took the reins and built one for themselves. He was also an investor and became a part-owner of the Savery Hotel.
He enjoyed traveling and later in life, he took his family, accompanied by four young ladies, for a year-long trip to Europe.
In 1905 Witmer built his home in what is now Owl's Head historic district. The House was designed by Des Moines architects Liebbe, Nourse, and Rasmussen.
The Witmer House began as a family home and has since served as the governor's mansion and as the offices of the Iowa High School Girl's Athletic Association. In 2012 it became a private residence, once again.
The Historic American Buildings Survey describes the home's construction as "a fine example of the Georgian Revival style that became prominent in the first third of the twentieth century."