The Island Woolen Company Office Building is located on the west bank of the Baraboo River, about two-thirds of a mile west of downtown Baraboo. It is the only remaining building of the former Island Woolen Company mill complex, which ran along the river, north of the existing building. The reference to the "island" on which the mill originally stood was based on the site when it was first developed in the 1850s. A raceway was cut from above a dam upstream and ran to the east across the oxbow toward the mill downstream. The mill raceway had long ago been filled in and no trace is readily visible.

The construction of the office building began in September 1917, and the building was largely completed in early 1918. It was built as the southernmost attachment to an older office and factory building. The Madison architectural firm of Claude & Starck designed the Prairie School style building. Louis Ward Claude, a native of the Baraboo area, was a life-long friend of Island Woolen Company Vice President, William Henry McFetridge.

It was noted in an August 30, 1917 newspaper article that it was to be "a modern structure in every way." The ground floor was to be used for administrative offices, and the second floor was to be used for an employee lunchroom, reading room, and a nursing station. The lower level served as a garage and storage space.

The building currently is being renovated for use as the Sauk County History Center.