Inigo Lopez de Loyola (sometimes erroneously called Inigo Lopez de Recalde) was born in the municipality of Azpeitia at the castle of Loyola in today's Gipuzkoa, Basque Country, Spain. He was baptized Inigo, after St. Enecus (Innicus) (Basque: Eneko; Spanish: Inigo) Abbot of Ona, a medieval Basque name which perhaps means "My little one". It is not clear when he began using the Latin name "Ignatius" instead of his baptismal name "Inigo". It seems he did not intend to change his name, but rather adopted a name which he believed was a simple variant of his own, for use in France and Italy where it was better understood.

As a boy Inigo became a page in the service of a relative, Juan Velazquez de Cuellar, treasurer (contador mayor) of the kingdom of Castile.  As a young man Inigo had a great love for military exercises as well as a tremendous desire for fame. He framed his life around the stories of El Cid, the knights of Camelot, and the Song of Roland. He joined the army at seventeen, and according to one biographer, he strutted about "with his cape slinging open to reveal his tight-fitting hose and boots; a sword and dagger at his waist". According to another he was "a fancy dresser, an expert dancer, a womanizer, sensitive to insult, and a rough punkish swordsman who used his privileged status to escape prosecution for violent crimes committed with his priest brother at carnival time." Upon encountering a Moor who denied the divinity of Jesus, he challenged him to a duel to the death, and ran him through with his sword. He dueled many other men as well.  In 1509, at the age of 18, Inigo took up arms for Antonio Manrique de Lara, Duke of Najera. His diplomacy and leadership qualities earned him the title "servant of the court", which made him very useful to the Duke. Under the Duke's leadership, Inigo participated in many battles without injury. But at the Battle of Pamplona in 1521 he was gravely injured when a French-Navarrese expedition force stormed the fortress of Pamplona on May 20, 1521. A cannonball hit him in the legs, wounding his right leg and fracturing the left in multiple places. Inigo was returned to his father's castle in Loyola, where, in an era that knew nothing of anesthetics, he underwent several surgical operations to repair his legs, having the bones set and then rebroken. In the end these operations left one leg shorter than the other: Inigo would limp for the rest of his life, and his military career was over.

Did he recover?
In the end these operations left one leg shorter than the other: Inigo would limp for the rest of his life, and his military career was over.