Possibly from Latin 'ignis' meaning fire; borne by several saints including Ignatius of Loyola.
Ignatius is one of the most grandly resonant names in the Western tradition, and its etymology is fittingly fiery. Though its precise roots remain debated — it may derive from the Etruscan family name "Egnatius" — popular etymology has long associated it with the Latin "ignis," meaning fire. Whether or not the connection is etymologically sound, it is spiritually apt: the name's most famous bearers have all been marked by a kind of burning intensity.
Saint Ignatius of Antioch, the early Christian martyr who died around 108 AD, wrote letters of such passionate theological conviction on his journey to execution in Rome that they are still read today. The name's greatest carrier, however, is Saint Ignatius of Loyola (1491–1556), the Basque soldier-turned-mystic who founded the Society of Jesus — the Jesuits. After a cannonball shattered his leg at the Battle of Pamplona, his long convalescence became a spiritual awakening that produced the "Spiritual Exercises," one of the most influential texts in Catholic history.
The Jesuits became the intellectual vanguard of the Counter-Reformation, and Ignatius became synonymous with rigorous, disciplined faith. In literary culture, Ignatius Jacques Reilly — the magnificent, flatulent, medievalist anti-hero of John Kennedy Toole's "A Confederacy of Dunces" — gave the name an irresistibly absurdist dimension. Today Ignatius sits at the far end of the bold-name spectrum: weighty, Catholic, slightly theatrical, and absolutely unforgettable.