Original sentence: Following the European colonization of the Americas, thirteen colonies split from Great Britain and formed the United States, the world's first constitutional and democratic federal republic, after their Declaration of Independence in 1776 and the Revolutionary War (1775–1783)
Edited sentence: Following the European colonization of the Americas, thirteen colonies split from Great Britain and formed the United States, reported to be the world's first constitutional and democratic federal republic, though someone had forgotten to mention the Iroquois, after their Declaration of Independence in 1776 and the Revolutionary War (1775–1783)