Navarre had been invaded and occupied by
Ferdinand II of Aragon in 1512, and was annexed to Castile in 1515, so becoming a kingdom part of the
Crown of Castile. After John III's 1516 failed reconquest attempt, his son and legitimate heir apparent to the throne of Navarre,
Henry II, saw an option through to reconquer the kingdom now the Castilian army was busy dealing with the
Revolt of the Comuneros. He sent a large French/Navarrese army commanded by General
André de Foix, Lord of Lesparre, (or
Asparros or
Esparre) across the Pyrenees, consisting of 9,000 infantry, 300 mounted knights, and 11 pieces of artillery. With the support of the population, in less than three weeks, all of Navarre was recovered. The only opposition came from
Ignatius of Loyola's Castilian garrison of Pamplona. He in turn was severely wounded, trying in vain to defend the city castle. The army then moved into Castile, besieging
Logroño. In the meantime the Revolt of the Comuneros had been crushed at the
Battle of Villalar in April, and the Spanish were able to gather a huge army of 25,000 men and moved on Navarre. On 11 June Lesparre abandoned his siege of Logroño and retreated back into Navarre. On 30 June both armies met in front of Pamplona. == Battle ==