What document did the United States celebrate 200 years after its 1776 adoption, before America250?

The document celebrated at the United States Bicentennial was the United States Declaration of Independence.

The Bicentennial marked 200 years since the Second Continental Congress adopted the declaration on July 4, 1776. America250 carries the same anniversary tradition forward by commemorating 250 years in 2026.

The declaration and the Constitution are related but serve different purposes. The declaration announced separation from Great Britain and explained the reasons for independence. The Constitution, signed in 1787, established the framework of the federal government. The Articles of Confederation preceded the Constitution as the first U.S. governing charter.

The declaration has remained central to national commemorations because it expresses the political break that created the United States. Its anniversary is therefore the specific historical basis for America250, rather than the later ratification of the Constitution or the end of the Revolutionary War.