In 1856, Stiles moved to Wapello County, Iowa, and taught school the following winter.

He studied law with Colonel S. W. Summers of Ottumwa, Iowa, and was admitted to the bar in 1857.

He stumped for Stephen A. Douglas in Iowa alongside Henry Clay Dean for the 1860 presidential election.

In 1865, Stiles was elected to the Iowa Senate, serving in the 1866 session but ultimately resigned in 1866 after his nomination to the Republican State Convention as reporter for the Supreme Court.

Stiles prepared and published Recollections and Sketches of Notable Lawyers and Public Men of Early Iowa in 1916.

[1][4] Stiles married Emma M. Vernon of Chester County, Pennsylvania, on September 19, 1861.