He was born in Cáceres, the son of Don Juan de Sande, second señor de Valhondo. Don Alvaro de Sande participated in numerous campaigns in the Spanish Army, including the Conquest of Tunis (1535), the conquest of Düren and Roermond in 1543, and the grand Battle of Mühlberg in 1549, in which Sande distinguished himself. When the German Campaign ended, Sande fought in the Italian War of 1551–1559 against France in the Tercios of Milan.