The Action of 28 November 1751 was a naval engagement off Cape St. Vincent between a squadron of two Spanish ships of the line under captain Pedro Fitz-James Stuart and an Algerine squadron of two ships of the line under corsair Mohammed Chirif, which was fought from November 28 to December 2, 1751 and resulted in a victory for the Spanish fleet. The Algerine ships had come from the port of Algiers, and were acting as corsairs, conducting commerce raiding against Christian merchant ships and enslaving their crews. This was part of the Barbary slave trade, where the Barbary states, autonomous vassals of the Ottoman Empire raided Christian settlements and merchant vessels for slaves to sell in their own cities. The corsairs targeted Spain, a Christian country, and the Spanish Navy was sent to track down the formidable Algerine force of two ships of the line, which posed a significant threat to any Christian vessels in the region. When the fleets sighted each other on November 28, 1751, they found that they were evenly matched with their opposition; both fielded two ships of the line.