Final answer:
The plan to unite the colonies in a “firm league of friendship” was known as the Articles of Confederation. It served as the first constitution of the United States and established a weak central government.
Step-by-step explanation:
The plan to unite the colonies in a “firm league of friendship” was known as the Articles of Confederation. This document served as the first constitution of the United States and was adopted by the Continental Congress in 1777. The Articles of Confederation established a weak central government and granted most powers to the individual states. However, it proved ineffective and was eventually replaced by the U.S. Constitution.
Learn more about The Articles of Confederation