American Revolutionary War: American forces under George Clark capture Kaskaskia during the Illinois campaign.
The Illinois campaign, also known as Clark's Northwestern campaign (1778-1779), was a series of events during the American Revolutionary War in which a small force of Virginia militiamen, led by George Rogers Clark, seized control of several British posts in the Illinois Country of the Province of Quebec, in what are now Illinois and Indiana in the Midwestern United States. The campaign is the best-known action of the western theater of the war and the source of Clark's reputation as an early American military hero.
In July 1778, Clark and his men crossed the Ohio River from Kentucky and took control of Kaskaskia, Vincennes, and several other villages in British territory. The occupation was accomplished without firing a shot because most of the Canadien and Native American inhabitants, who peacefully co-existed with one another, were unwilling to take up arms on behalf of the British Empire. To counter Clark's advance, Henry Hamilton, the British lieutenant governor at Fort Detroit, reoccupied Vincennes with a small force. In February 1779, Clark returned to Vincennes in a surprise winter expedition and retook the town, capturing Hamilton in the process. Virginia capitalized on Clark's success by establishing the region as Illinois County, Virginia.
The importance of the Illinois campaign has been the subject of much debate. Because the British ceded the entire Northwest Territory to the United States in the 1783 Treaty of Paris, some historians have credited Clark with nearly doubling the size of the original Thirteen Colonies by seizing control of the Illinois Country during the war. For this reason, Clark was nicknamed the "Conqueror of the Northwest", and his Illinois campaignparticularly the surprise march to Vincenneswas greatly celebrated and romanticized.
The American Revolutionary War (April 19, 1775 – September 3, 1783), also known as the Revolutionary War or American War of Independence, secured a United States of America independent from Great Britain. Fighting began on April 19, 1775, followed by the Declaration of Independence on July 4, 1776. The American Patriots were supported by France and Spain, conflict taking place in North America, the Caribbean, and Atlantic Ocean. It ended on September 3, 1783 when Britain accepted American independence in the Treaty of Paris, while the Treaties of Versailles resolved separate conflicts with France and Spain.Established by Royal charter in the 17th and 18th centuries, the American colonies were largely autonomous in domestic affairs and commercially prosperous, trading with Britain and its Caribbean colonies, as well as other European powers via their Caribbean entrepôts. After British victory in the Seven Years' War in 1763, tensions arose over trade, colonial policy in the Northwest Territory and taxation measures, including the Stamp Act and Townshend Acts. Colonial opposition led to the 1770 Boston Massacre and 1773 Boston Tea Party, with Parliament responding by imposing the so-called Intolerable Acts.
On September 5, 1774, the First Continental Congress drafted a Petition to the King and organized a boycott of British goods. Despite attempts to achieve a peaceful solution, fighting began with the Battle of Lexington on April 19, 1775 and in June Congress authorized George Washington to create a Continental Army. Although the "coercion policy" advocated by the North ministry was opposed by a faction within Parliament, both sides increasingly viewed conflict as inevitable. The Olive Branch Petition sent by Congress to George III in July 1775 was rejected and in August Parliament declared the colonies to be in a state of rebellion.
Following the loss of Boston in March 1776, Sir William Howe, the new British commander-in-chief, launched the New York and New Jersey campaign. He captured New York City in November, before Washington won small but significant victories at Trenton and Princeton, which restored Patriot confidence. In summer 1777, Howe succeeded in taking Philadelphia, but in October a separate force under John Burgoyne was forced to surrender at Saratoga. This victory was crucial in convincing powers like France and Spain an independent United States was a viable entity.
France provided the US informal economic and military support from the beginning of the rebellion, and after Saratoga the two countries signed a commercial agreement and a Treaty of Alliance in February 1778. In return for a guarantee of independence, Congress joined France in its global war with Britain and agreed to defend the French West Indies. Spain also allied with France against Britain in the Treaty of Aranjuez (1779), though it did not formally ally with the Americans. Nevertheless, access to ports in Spanish Louisiana allowed the Patriots to import arms and supplies, while the Spanish Gulf Coast campaign deprived the Royal Navy of key bases in the south.
This undermined the 1778 strategy devised by Howe's replacement, Sir Henry Clinton, which took the war into the Southern United States. Despite some initial success, by September 1781 Cornwallis was besieged by a Franco-American force in Yorktown. After an attempt to resupply the garrison failed, Cornwallis surrendered in October, and although the British wars with France and Spain continued for another two years, this ended fighting in North America. In April 1782, the North ministry was replaced by a new British government which accepted American independence and began negotiating the Treaty of Paris, ratified on September 3, 1783.