Henry Anson Castle moved to Minnesota in 1866 to recuperate from injuries sustained in the Civil War. For the next four decades, he practiced law in St. Paul, engaged in various businesses and real estate development, owned and edited newspapers, served in the state legislature and was a hard-working, honest civil servant. His great passion was politics or, more accurately, Republican Party politics.
In 1907, he delivered his "Reminiscences of Minnesota Politics" to the Minnesota Historical Society, which published an expanded version in 1915. The title is a bit overbroad because the subject of his memoir is the internal affairs of the Republican Party from the mid-1860s to 1904 when he retired to write local history. It is an insider's account of fierce contests within the party for endorsements for state offices at the biennial party conventions and within the party-controlled state legislature for elections of U. S. Senator. Woven throughout is the story of the rise to political prominence and power of one of the state's most remarkable lawyers: Cushman Kellogg Davis.
Henry Castle's memoir of Minnesota Republican politics in the nineteenth century is anecdotal, frank, engaging, insightful, often fascinating and well written.