Early on it was used as a campground for newly arrived Mormon pioneers, and wagon trains headed to other areas of the Western United States.

[9] The DUP monument erroneously claims the first group of Mormon pioneers who arrived in July 1847 camped at the square.

Later the square became the site of a skating pond, was used as circus grounds, hosted a marketplace for hay, and for a time included a baseball park.

[10] Some sources indicate the block had been named "Washington Square" on December 12, 1865 by the Salt Lake City Council, and simply needed reconfirmation in 1957.

[12][13] As part of the 2002 Olympic torch relay, a special cauldron was set up on the square, which was lit by Paralympic athlete Chris Waddell during a celebration in front of the City and County Building on February 7, 2002.

A similar event occurred on July 24, 2024, when thousands gathered on the east side of Washington Square for a "Celebrate 2034" party, to watch coverage from Paris of the bid announcement for the 2034 Winter Olympics.