Beauregard played a role in shaping the 'Lost Cause' narrative of the Civil War, which romanticized the Confederacy and minimized the role of slavery. This narrative influenced how the war was remembered in the South.

Numerous monuments and memorials were erected in Beauregard's honor, particularly in the South. However, in recent years, some of these monuments have been removed due to changing attitudes towards Confederate symbols. His legacy remains complex and contested.