Peirce Mansion, Romanesque Revival mansion in Sioux City, United States.

Peirce Mansion is a 23-room Romanesque Revival house built of Sioux Quartzite in 1893 for financier John Peirce. It stands in Sioux City, Iowa, and has been restored to a Victorian-era appearance.

John Peirce, a financier, built the Romanesque mansion of Sioux Quartzite in 1893 with 23 rooms. The Junior League bought it in 1959, and it opened as the Sioux City Public Museum in September 1960. The museum moved downtown to a former J. C. Penney store in 2011, and the mansion was listed on the National Register of Historic Places in 1978.

The Junior League bought the house in 1959, and it opened as the Sioux City Public Museum in September 1960, showing exhibits on regional history. In 1996 a saddlebag was stolen from the museum, one of a series of thefts of Native American artifacts. The museum moved downtown in 2011 to a former J. C. Penney store.

The ground floor is accessible for visitors with mobility needs, making it easy to see the main spaces without climbing stairs. Visiting is typically done through guided tours rather than self-directed exploration, so planning ahead helps you make the most of your time there.

The mansion was bought by the Junior League in 1959 and opened as the Sioux City Public Museum in September 1960, a role it kept until 2011. In 1996 a saddlebag was stolen from the museum during a series of thefts of Native American artifacts.