Frey Juan Del Águila y Arellano (Ávila, 1545 - A Coruña, August 1602) was a Spanish general. He commanded the Spanish expeditionary Tercio troops in Sicily then in Brittany (1584–1598, also sending a detachment to raid England), before serving as general of the Spanish armies in the invasion of Ireland (1600–1602). As a soldier, and subsequently Field Master of the Tercios, he was posted to Sicily, Africa, Malta, Corsica, the Milanese, the Netherlands, Spain, Portugal, France and Ireland, where he participated in major military events of his time, such as the Siege of Malta, the Looting of Antwerp, the Siege of Antwerp, the Miracle of Empel, the Expedition in support of French Catholics, the Battle of Cornwall and the Expedition to support the Irish.