The United States’ previous major national anniversary in 1976 was the Bicentennial.
The Bicentennial marked 200 years since the Declaration of Independence in 1776. Its principal anniversary year was 1976, exactly two centuries after the founding-era events commemorated by Independence Day. The 2026 Semiquincentennial follows the same chronological pattern at the 250-year mark.
The 1976 celebration was a major nationwide event involving exhibitions, parades, public works, historical programs, and special commemorative items. The federal government and communities across the country used the occasion to highlight American history and national identity.
The terms can be confused because they describe different intervals. A centennial is 100 years, a bicentennial is 200, a semiquincentennial is 250, and a tricentennial is 300. Thus, 1976 was the Bicentennial, while 2026 is America’s Semiquincentennial.