The Seven Years' War (17561763) was a global conflict between Great Britain and France for global pre-eminence. Britain, France and Spain fought both in Europe and overseas with land-based armies and naval forces, while Prussia sought territorial expansion in Europe and consolidation of its power. Long-standing colonial rivalries pitting Britain against France and Spain in North America and the West Indies were fought on a grand scale with consequential results. In Europe, the conflict arose from issues left unresolved by the War of the Austrian Succession (17401748). Prussia sought greater influence in the German states, while Austria wanted to regain Silesia, captured by Prussia in the previous war, and to contain Prussian influence.

In a realignment of traditional alliances, known as the Diplomatic Revolution of 1756, Prussia became part of a coalition led by Britain, which also included long-time Prussian competitor Hanover, at the time in personal union with Britain. At the same time, Austria ended centuries of conflict between the Bourbon and Habsburg families by allying with France, along with Saxony, Sweden and Russia. Spain aligned formally with France in 1762. Spain unsuccessfully attempted to invade Britain's ally Portugal, attacking with their forces facing British troops in Iberia. Smaller German states either joined the Seven Years' War or supplied mercenaries to the parties involved in the conflict.

Anglo-French conflict over their colonies in North America had begun in 1754 in what became known in the United States as the French and Indian War (175463), which became a theatre of the Seven Years' War, and ended France's presence as a land power on that continent. It was "the most important event to occur in eighteenth-century North America" prior to the American Revolution. Spain entered the war in 1761, joining France in the Third Family Compact between the two Bourbon monarchies. The alliance with France was a disaster for Spain, with the loss to Britain of two major ports, Havana in the West Indies and Manila in the Philippines, returned in the 1763 Treaty of Paris between France, Spain and Great Britain. In Europe, the large-scale conflict that drew in most of the European powers was centered on the desire of Austria (long the political centre of the Holy Roman Empire of the German nation) to recover Silesia from Prussia. The Treaty of Hubertusburg ended the war between Saxony, Austria and Prussia, in 1763. Britain began its rise as the world's predominant colonial and naval power. France's supremacy in Europe was halted until after the French Revolution and the emergence of Napoleon Bonaparte. Prussia confirmed its status as a great power, challenging Austria for dominance within the German states, thus altering the European balance of power.

Frederick II (German: Friedrich II.; 24 January 1712 – 17 August 1786) was King in Prussia from 1740 until 1772, and King of Prussia from 1772 until his death. His most significant accomplishments include his military successes in the Silesian wars, his re-organisation of the Prussian Army, the First Partition of Poland, and his patronage of the arts and the Enlightenment. Frederick was the last Hohenzollern monarch titled King in Prussia and declared himself King of Prussia after annexing Polish Prussia from the Polish–Lithuanian Commonwealth in 1772. Prussia greatly increased its territories and became a major military power in Europe under his rule. He became known as Frederick the Great (German: Friedrich der Große) and was nicknamed "The Old Fritz" (German: "Der Alte Fritz").

In his youth, Frederick was more interested in music and philosophy than the art of war, which led to clashes with his authoritarian father, Frederick William I of Prussia. However, upon ascending to the Prussian throne, he attacked and annexed the rich Austrian province of Silesia in 1742, winning military acclaim for himself and Prussia. He then became an influential military theorist whose analysis emerged from his extensive personal battlefield experience and covered issues of strategy, tactics, mobility and logistics.

Frederick was a supporter of enlightened absolutism, stating that the ruler should be the first servant of the state. He modernised the Prussian bureaucracy and civil service, and pursued religious policies throughout his realm that ranged from tolerance to segregation. He reformed the judicial system and made it possible for men of lower status to become judges and senior bureaucrats. Frederick also encouraged immigrants of various nationalities and faiths to come to Prussia, although he enacted oppressive measures against Catholics in Silesia and Polish Prussia. He supported the arts and philosophers he favoured, and allowed freedom of the press and literature. Frederick was almost certainly homosexual, and his sexuality has been the subject of much study. He is buried at his favourite residence, Sanssouci in Potsdam. Because he died childless, he was succeeded by his nephew, Frederick William II.

Nearly all 19th-century German historians made Frederick into a romantic model of a glorified warrior, praising his leadership, administrative efficiency, devotion to duty and success in building Prussia into a great power in Europe. Frederick remained an admired historical figure through Germany's defeat in World War I, and the Nazis glorified him as a great German leader pre-figuring Adolf Hitler, who personally idolised him. His reputation became less favourable in Germany after World War II, partly due to his status as a Nazi symbol. Regardless, historians in the 21st century tend to view Frederick as an outstanding military leader and capable monarch, whose commitment to enlightenment culture and administrative reform built the foundation that allowed the Kingdom of Prussia to contest the Austrian Habsburgs for leadership among the German states.