Founder William Penn had a plan for Philadelphia. He wanted a prosperous, bustling city with straight, orderly streets. He also set aside five squares, establishing parks for the public. Both ideas influenced the design of many later American towns and cities.
Southeast Square, renamed for George Washington in 1825, only slowly lived up to Penn's ideal. In the 18th century, it served as a burial ground and pasture. In the 19th century the city added trees, walks, benches, lamps, and an ornamental fence. An 1846 guidebook described the Square as "beautiful and fashionable."
In the mid-2oth century, residents added the memorial to Washington and unknown soldiers of the American Revolution. It remains the Square's centerpiece.
The Square's importance to the nation was formally recognized when it became part of Independence National Historical Park at the beginning of the 21st century.