No Peace Without Spain was a popular British political slogan of the early eighteenth century. It referred to the ongoing War of the Spanish Succession (1701–1714) in which Britain was a leading participant. It implied that no peace treaty could be agreed with Britain's principal enemy Louis XIV of France that allowed Philip, the French candidate, to retain the Spanish crown. The term became a rallying cry for opposition to the Tory government of Robert Harley, Earl of Oxford, and the terms of the Treaty of Utrecht.

The phrase was first popularly used by the Tory politician Lord Nottingham in Parliament in December 1711. However it was soon adopted by the rival Whig movement, who were increasingly regarded as the "war party" opposed to the "peace party" of the Tories. The Whigs were buoyed by the campaigns in the Low Countries where the British commander, the Duke of Marlborough, led the Allies to a series of victories. The Whigs demanded that King Louis be made to abandon his expansionist policies, and renounce any attempts to make Spain a satellite state.

While the term originated in London, it also spread to several Allied capitals as a statement of intent. However, this represented an extension of the war aims the Allies had originally agreed upon, potentially extending the conflict.

The intervention in Spain started well for the pro-Habsburg side, with the capture of Gibraltar in 1704 and Barcelona in 1705 and securing the support of Portugal and Catalonia. However, it soon became clear the Bourbon candidate Philip V was far more popular in Castile than the Austrian Archduke Charles. The Allies were forced to evacuate Madrid in 1706 and soundly beaten at the Battle of Almansa in 1707.

In 1708 the new British commander James Stanhope took the island of Minorca, a possession of more use to the British than Charles' prospects of becoming King of Spain. Philip's forces recaptured Alicante in April 1709 and defeated an Anglo-Portuguese army at La Gudiña in May. The Portuguese now declared an informal truce, allowing trade and agriculture to recommence.

A renewed Allied effort in 1710 led to victories at Almenar and Saragossa in July and August and the capture of Madrid in September. However, lack of support from the local population meant Charles entered an almost deserted city and the Allies were effectively isolated when Portuguese forces were prevented from crossing into Spain. In November, they left Madrid for Catalonia in two separate detachments, Stanhope's division of 5,000 and one of 12,000 under the Austrian Starhemberg. At Brihuega on 9 December 1710, Stanhope was taken by surprise and forced to surrender to an army led by Louis Joseph, Duke of Vendôme. Vendôme followed this up the next day by defeating Starhemberg at Villaviciosa; these defeats were a devastating setback to Allied ambitions in Spain.

In April 1711, Emperor Joseph I died and his brother Archduke Charles succeeded him as the Holy Roman Emperor Charles VI; an Austrian union with Spain was as unwelcome to Britain as a French one, which meant to many strategists there seemed little point in continuing the war.

A new Tory government, led by Robert Harley, came to power in 1710. Committed to ending Britain's involvement in the European war, which had been costly in lives and money, it took steps to disengage, which eventually resulted in the dismissal of the hawkish Marlborough, who was replaced by the Irish Tory commander, the Duke of Ormonde.