American Revolution: Louis XVI of France declares war on the Kingdom of Great Britain.

Louis XVI (Louis-Auguste; French pronunciation: [lwi sz]; 23 August 1754 21 January 1793) was the last King of France before the fall of the monarchy during the French Revolution. He was referred to as Citizen Louis Capet during the four months just before he was executed by guillotine. He was the son of Louis, Dauphin of France, son and heir-apparent of King Louis XV, and Maria Josepha of Saxony. When his father died in 1765, he became the new Dauphin. Upon his grandfather's death on 10 May 1774, he assumed the title King of France and Navarre until 4 September 1791, when he received the title of King of the French until the monarchy was abolished on 21 September 1792.

The first part of his reign was marked by attempts to reform the French government in accordance with Enlightenment ideas. These included efforts to abolish serfdom, remove the taille (land tax) and the corve (labour tax), and increase tolerance toward non-Catholics as well as abolish the death penalty for deserters. The French nobility reacted to the proposed reforms with hostility, and successfully opposed their implementation. Louis implemented deregulation of the grain market, advocated by his economic liberal minister Turgot, but it resulted in an increase in bread prices. In periods of bad harvests, it led to food scarcity which, during a particularly bad harvest in 1775, prompted the masses to revolt. From 1776, Louis XVI actively supported the North American colonists, who were seeking their independence from Great Britain, which was realised in the 1783 Treaty of Paris. The ensuing debt and financial crisis contributed to the unpopularity of the Ancien Rgime. This led to the convening of the Estates-General of 1789. Discontent among the members of France's middle and lower classes resulted in strengthened opposition to the French aristocracy and to the absolute monarchy, of which Louis and his wife Queen Marie Antoinette were viewed as representatives. Increasing tensions and violence were marked by events such as the storming of the Bastille, during which riots in Paris forced Louis to definitively recognize the legislative authority of the National Assembly.

Louis's indecisiveness and conservatism led some elements of the people of France to view him as a symbol of the perceived tyranny of the Ancien Rgime, and his popularity deteriorated progressively. His unsuccessful flight to Varennes in June 1791, four months before the constitutional monarchy was declared, seemed to justify the rumors that the king tied his hopes of political salvation to the prospects of foreign intervention. The credibility of the king was deeply undermined, and the abolition of the monarchy and the establishment of a republic became an ever-increasing possibility. The growth of anti-clericalism among revolutionaries resulted in the abolition of the dme (religious land tax) and several government policies aimed at the dechristianization of France.

In a context of civil and international war, Louis XVI was suspended and arrested at the time of the Insurrection of 10 August 1792. One month later, the monarchy was abolished and the First French Republic was proclaimed on 21 September 1792. Louis was then tried by the National Convention (self-instituted as a tribunal for the occasion), found guilty of high treason and executed by guillotine on 21 January 1793, as a desacralized French citizen under the name of Citizen Louis Capet, in reference to Hugh Capet, the founder of the Capetian dynasty which the revolutionaries interpreted as Louis's surname. Louis XVI was the only king of France ever to be executed, and his death brought an end to more than a thousand years of continuous French monarchy. Both of his sons died in childhood, before the Bourbon Restoration; his only child to reach adulthood, Marie Thrse, was given over to the Austrians in exchange for French prisoners of war, eventually dying childless in 1851.

The American Revolution was an ideological and political revolution that occurred in British America between 1765 and 1791. The Americans in the Thirteen Colonies formed independent states that defeated the British in the American Revolutionary War (1775–1783), gaining independence from the British Crown, establishing the constitution that created the United States of America, the first modern constitutional liberal democracy.American colonists objected to being taxed by the British Parliament, a body in which they had no direct representation. Before the 1760s, Britain's American colonies had enjoyed a high level of autonomy in their internal affairs, which were locally governed by colonial legislatures. The passage of the Stamp Act of 1765 imposed internal taxes on official documents and newspapers printed in the colonies, which led to colonial protest, and the meeting of representatives of several colonies in the Stamp Act Congress. Tensions relaxed with the British repeal of the Stamp Act, but flared again with the passage of the Townshend Acts in 1767. The British government deployed troops to Boston in 1768 to quell unrest, leading to the Boston Massacre in 1770. The British government repealed most of the Townshend duties in 1770, but retained the tax on tea in order to symbolically assert Parliament's right to tax the colonies. The burning of the Gaspee in Rhode Island in 1772, the passage of the Tea Act of 1773 and the Boston Tea Party in December 1773 led to a new escalation in tensions. The British responded by closing Boston Harbor and enacting a series of punitive laws which effectively rescinded Massachusetts Bay Colony's privileges of self-government. The other colonies rallied behind Massachusetts, and twelve of the thirteen colonies sent delegates in late 1774 to form a Continental Congress for the coordination of their resistance to Britain. Opponents of Britain were known as Patriots or Whigs, while colonists who retained their allegiance to the Crown were known as Loyalists or Tories.

Open warfare erupted when British regulars sent to capture a cache of military supplies were confronted by local Patriot militia at Lexington and Concord on April 19, 1775. Patriot militia, joined by the newly formed Continental Army, then put British forces in Boston under siege by land and their forces withdrew by sea. Each colony formed a Provincial Congress, which assumed power from the former colonial governments, suppressed Loyalism, and contributed to the Continental Army led by Commander in Chief General George Washington. The Patriots unsuccessfully attempted to invade Quebec and rally sympathetic colonists there during the winter of 1775–76.

The Continental Congress declared British King George III a tyrant who trampled the colonists' rights as Englishmen, and they pronounced the colonies free and independent states on July 4, 1776. The Patriot leadership professed the political philosophies of liberalism and republicanism to reject rule by monarchy and aristocracy. The Declaration of Independence proclaimed that all men are created equal, though it was not until later centuries that constitutional amendments and federal laws would increasingly grant equal rights to African Americans, Native Americans, poor white men, and women.

The British captured New York City and its strategic harbor in the summer of 1776, which they held for the duration of the war. The Continental Army captured a British army at the Battle of Saratoga in October 1777, and France then entered the war as an ally of the United States, expanding the war into a global conflict. The British Royal Navy blockaded ports and captured New York City for the duration of the war, and other cities for brief periods, but they failed to destroy Washington's forces. Britain also attempted to hold the Southern states with the anticipated aid of Loyalists, and the war moved south. British general Charles Cornwallis captured an American army at Charleston, South Carolina in early 1780, but he failed to enlist enough volunteers from Loyalist civilians to take effective control of the territory. Finally, a combined American and French force captured Cornwallis' army at Yorktown in the fall of 1781, effectively ending the war. The Treaty of Paris was signed on September 3, 1783, formally ending the conflict and confirming the new nation's complete separation from the British Empire. The United States took possession of nearly all the territory east of the Mississippi River and south of the Great Lakes, with the British retaining control of northern Canada, and Spain taking back Florida.

Among the significant results of the war were American independence and the end of British mercantilism in America, opening up worldwide trade for the United States - including with Britain. Around 60,000 Loyalists migrated to other British territories, particularly to Canada, but the great majority remained in the United States. The Americans soon adopted the United States Constitution, replacing the weak wartime Confederation and establishing a comparatively strong national government structured as a federal republic, which included an elected executive, a national judiciary, and an elected bicameral Congress representing states in the Senate and the population in the House of Representatives. It is the world's first federal democratic republic founded on the consent of the governed. Shortly after a Bill of Rights was ratified as the first ten amendments, guaranteeing fundamental rights used as justification for the revolution.