Seven Years' War, worldwide series of conflicts fought from 1756 to 1763 for the control of Germany and for supremacy in colonial North America and India. It involved most of the major powers of Europe, in particular Prussia, Great Britain, and Hannover on one side and Austria, Saxony, France, Russia, Sweden, and Spain on the other. The North American segment of the conflict, known as the French and Indian War, involved Great Britain and its American colonies against the French and their Algonquian allies. The Indian phase established British domination in India.

Austria's resolve to repossess the rich province of Silesia, which had been lost to Prussia in 1748, was the major conflict leading to the Seven Years' War. Maria Theresa, archduchess of Austria and queen of Hungary and Bohemia, acquired the support of Russia, Sweden, Saxony, Spain, and France, with the specific aim of waging war against Prussia and its ally, Great Britain. It was Frederick II of Prussia, however, who initiated the hostilities with his attack and capture of Saxony in 1756.

Through the first half of the war, the Prussians continued victorious. They defeated the French at Rossbach and the Austrians at Leuthen in 1757 and the Russians at Zorndorf in 1758. At this point, however, with Sweden entering the war and virtually all Europe opposing Frederick, the tide seemed to turn. By 1759 eastern Prussia was in the hands of the Russians, and Berlin had been captured. The Prussian situation was desperate. Two significant factors, however, led to the eventual return of Prussian dominance in the war. One was the active support of the British and Hannoverians; both, until this point ineffective combatants, now fought successfully against the French. The second, and more important, was the withdrawal in 1762 of Russia and Sweden from the war. This occurred as a result of the death of Elizabeth Petrovna, empress of Russia; her successor, Peter III, an admirer of Frederick, quickly signed a peace treaty with the Prussian leader.

In North America, the war began in 1754. Colonial rivalry had gradually developed between France and Great Britain over lucrative fur-trading posts and land west of the Appalachian Mountains and over fishing rights off the coast of Newfoundland. The French, by a strategy of encirclement, hoped to contain English settlement, particularly in the Ohio Valley, where Virginia planters had established fur-trading posts in 1749. By resisting British expansion westward, France was in hopes of uniting, through a chain of forts, its Canadian empire with possessions as far south as New Orleans.

During the first two years of the war, French and Native American forces were largely victorious, winning an important and surprising victory in defending Fort Duquesne. In 1757, however, the British statesman William Pitt the Elder, a pro-Prussian, was given complete charge of British foreign policy and appointed the British general James Wolfe to command the troops in the New World. Pitt's bold strategy ultimately resulted in defeat for the French. By 1760 the British had conquered all of French Canada.

Britain was also victorious in India, completely demolishing French plans for control of the country. Responsible for much of the success was the British soldier Robert Clive. The most important event of the war was the Battle of Plassey.

The Seven Years' War officially ended in 1763. On February 10 of that year the Treaty of Paris was signed to settle differences between France, Spain, and Great Britain. Among the terms was the acquisition of almost the entire French Empire in North America by Great Britain. The British also acquired Florida from Spain, and the French retained their possessions in India only under severe military restrictions. The continent of Europe remained free from territorial changes.

On February 15, the Treaty of Hubertusburg was signed at Hubertusburg, Saxony. This agreement confirmed Prussia's possession of Silesia, and established it as a leading power in Europe.