Santiago! (or ¡Santiago y cierra, España!), is an alleged war cry of Iberian troops during the Reconquista, and of the Spanish Empire. In English, it is often translated as "Santiago and close, Spain!" or "Santiago and at them, Spain!"
Supposedly, its first usage was during the Battle of Las Navas de Tolosa, and was utilized in each occasion that Spanish troops fought Muslims. The meaning of the phrase is to praise St. James the apostle, patron saint of Spain, and to charge or to attack ("close in on them!"). The "Spain", in the end, refers to the recipient of the phrase: the Spanish troops.
After the Reconquista, the phrase continued to be used, especially by the brigades of Spanish cavalry and the Conquistadores under Hernán Cortés. Cervantes quotes it in Don Quixote, when the knight and Sancho Panza are discussing Santiago.