First, Native Americans originally migrated to North America across the Bering Land Bridge millions of years ago. Europeans then began arriving in the late 1500s from Britain, France, and Spain to settle along the Atlantic coast and in the southern and southwestern US and northern areas for land, minerals, and freedom. The 13 British colonies gained independence from Britain through the Revolutionary War between 1775-1783, forming the United States. Other British colonies in Canada became the self-governing Dominion of Canada in 1867. Both countries expanded westward in the 1800s, transformed by industrialization powered by waterfalls and coal, and the growth of cotton agriculture and railroads.