English expedition to Portugal (1662–1668)

The English expedition to Portugal also known as the British Brigade in Portugal was a brigade raised during the reign of King Charles II for service in Portugal during the ongoing Portuguese Restoration War against Spain in August 1662. The brigade, many of which were veterans of the English Civil Wars and the Dutch Revolt, then fought in all the major battles and skirmishes under the command of Frederick Schomberg, 1st Duke of Schomberg and remained in Portugal until the end of the war being subsequently disbanded by mid 1668. The brigade under Schomberg's leadership, proved a decisive factor in winning back Portugal's independence.

The war between Portugal and Spain had begun with the Portuguese revolution of 1640 and had resulted in the break up of the Iberian Union. After the peace of the Pyrenees in 1659, the independence of Portugal was threatened by a resurgent Spain, and thus Portugal asked for outside support. They turned to their old ally England but the Restoration of Charles II as monarch of England proved a concern. He had previously been allied to Spain through the Treaty of Brussels after Oliver Cromwell's Republic had been at war with Spain. Charles however immediately annulled the treaty citing King Philip IV of Spain's failure to aid in his restoration and instead answered Portugal's call for help. His marriage with Catherine of Braganza, renewed the alliance between England and Portugal despite the protestations of Spain. As part of the treaty a brigade was raised for service in Portugal in 1662 to help win her independence. The decision to send troops to Portugal came from the need to find employment for Cromwellian and Royalist veterans of the English Civil War, and the Portuguese military needed experienced veterans to help fight the Spanish.

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