Brittany campaign (1590–1598)
The Brittany campaign, or the campaign of Brittany, was a military occupation of Brittany, France, by Spain. It began in summer 1590 when Philippe-Emmanuel de Lorraine, Duke of Mercœur, the governor of Brittany, offered the port of Blavet to King Philip II of Spain so that he could harbour his fleet.
Source: Wikipedia — Brittany campaign (1590–1598) (CC BY-SA 4.0)