Friedrich Wilhelm August Heinrich Ferdinand von Steuben (born Friedrich Wilhelm Ludolf Gerhard Augustin Louis von Steuben; September 17, 1730 November 28, 1794), also referred to as Baron von Steuben (German: [fn tbm]), was a Prussian military officer who played a leading role in the American Revolutionary War by reforming the Continental Army into a disciplined and professional fighting force. His contributions marked a significant improvement in the performance of American troops, and he is subsequently regarded as one of the fathers of the United States Army.Born into a military family, Steuben was exposed to war from an early age; at 14 years old, he observed his father directing Prussian engineers in the 1744 siege of Prague. At age 16 or 17, he enlisted in the Prussian Army, which was considered the most professional and disciplined in Europe. During his 17 years of military service, Steuben took part in several battles in the Seven Years' War (175663), rose to the rank of captain, and became aide-de-camp to Prussian King Frederick the Great, who was renowned for his military prowess and strategy. Steuben's career culminated in his attendance of Frederick's elite school for young military officers, after which he was abruptly discharged from the army in 1763, allegedly by the machinations of a rival.Steuben spent 11 years as court chamberlain to the prince of Hohenzollern-Hechingen, a small German principality. In 1769, the Duchess of Wurttemburg, a niece of Frederick, named him to the chivalric Order of Fidelity, a meritorious award that conferred the title, Freiherr, or "free lord"; in 1771, his service to Hollenzollern-Hechingen earned him the title baron. In 1775, as the American Revolution had begun, Steuben saw a reduction in his salary and sought some form of military work; unable to find employment in peacetime Europe, he joined the American war effort through mutual French contacts with American diplomats, most notably ambassador to France Benjamin Franklin. Due to his military exploits, and his willingness to serve the Americans without compensation, Steuben made a positive impression on both Congress and General George Washington, who appointed him as temporary Inspector General of the Continental Army.

Appalled by the state of American forces, Steuben took the lead in teaching soldiers the essentials of military drills, tactics, and discipline based on Prussian techniques. He wrote Regulations for the Order and Discipline of the Troops of the United States, which remained the army's drill manual for decades, and continues to influence modern U.S. army manuals. Steuben also addressed widespread administrative waste and graft, helping save desperately needed supplies and funds. As these reforms began bearing fruit on the battlefield, in 1778, Congress, on Washington's recommendation, commissioned Steuben as Inspector General with the rank of Major General. He served the remainder of the war as Washington's chief of staff and one of his most trusted advisors.After the war, Steuben was made a U.S. citizen and granted a large estate in New York in reward for his service. In 1780, he was elected a member of the American Philosophical Society, a learned society that included most of the nation's most prominent founding fathers.

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.