The date of the start of the history of the United States is a subject of constant debate among historians. Older textbooks start with the arrival of Christopher Columbus in 1492 and emphasize the European background, or they start around 1600 and emphasize the American frontier. In recent decades American schools and universities typically have shifted back in time to include more on the colonial period and much more on the prehistory of the Native peoples.Indigenous people lived in what is now the United States for thousands of years before European colonists began to arrive, mostly from England, after 1600. The Spanish had small settlements in Florida and the Southwest, and the French along the Mississippi River and the Gulf Coast. By the 1770s, thirteen British colonies contained two and a half million people along the Atlantic coast east of the Appalachian Mountains.
In the 1760s the British government imposed a series of new taxes while rejecting the American argument that any new taxes had to be approved by the people (see Stamp Act 1765). Tax resistance, especially the Boston Tea Party (1774), led to punitive laws (the Intolerable Acts) by Parliament designed to end self-government in Massachusetts. American Patriots (as they called themselves) adhered to a political ideology called republicanism that emphasized civic duty, virtue, and opposition to corruption, fancy luxuries and aristocracy.