BRITISH RULE AND AMERICAN SETTLEMENT, 1765-1818
THE HISTORY OF Illinois between the French period and the time of statehood may be divided into three major phases: Illinois as a British possession, as part of Virginia, and as a territory of the United States. The "Illinois Country" was at first subjected to a measure of British sovereignty, extending formally from the Treaty of Paris of 1763 to the Treaty of Paris of 1783, but lasting in effect only from the arrival of British troops in 1765 to the conquests of George Rogers Clark in 1778-79. The State of Virginia, having sponsored Clark's expedition, then claimed the area by creating the County of Illinois. This arrangement lasted from 1778 to 1784, at which point Virginia ceded the land to the United States as organized under the Articles of Confederation. Finally, this cession, and the treaty of 1783, enabled the Confederation Congress, through the Northwest Ordinance of 1787, to chart steps toward the admission of Illinois into the Union in 1818.
The population of Illinois in the late colonial and early territorial periods was quite small. Estimated at 2,500 in 1752, not counting the Indians, it was no larger a half century later. Only at the end of the territorial period, especially after 1809, did the population grow substantially, exceeding 35,000 by 1818. Moreover, these Illinoisans were mostly clustered in a few villages along the Mississippi River. Yet they played a role in the larger imperial and national history of the period.
The colonial and territorial years were surveyed by several nineteenth-century writers, including, for example, John Reynolds, The Pioneer History of Illinois . . .