Under a provision allowed in the U.S. Articles of Confederation, Canada had an open invitation to join the United States. What Article allowed for this provision?

One mostly forgotten part of the Articles of Confederation, America’s first Constitution, was an open invitation for Canada to join the United States, with no strings attached.

The formal invitation to Canada officially initiated March 1, 1781, (when Maryland became the 13th state to ratify the document), was unique and came in the form of Article XI of the Articles of Confederation:

“Canada acceding to this confederation, and adjoining in the measures of the United States, shall be admitted into, and entitled to all the advantages of this Union; but no other colony shall be admitted into the same, unless such admission be agreed to by nine States.”

That provision allowed the residents of Canada to petition the U.S. for immediate inclusion in the United States. Any other British colony would have to be approved by 9 States.

The invitation stood open until the proposed (now current) U.S. Constitution was ratified in June 1788 and a new government took office in March 1789.