| # | Name | Origin | Meaning | Gender | |
|---|---|---|---|---|---|
| 581 | Ignacio | Latin | Fiery. St. Ignacius of Loyola was founder of the Catholic Jesuit order. | M | |
| 582 | Ignatius | Latin | Ardent. | M | |
| 583 | Ilari | Latin | Cheerful. | M | |
| 584 | Ilarion | Latin | Cheerful. | M | |
| 585 | Illan | Latin | Youth. | M | |
| 586 | Illian | Latin | Youth. | M | |
| 587 | Illius | Latin | Youth. | M | |
| 588 | Ilus | Latin | Founder of Troy. | M | |
| 589 | Inachus | Latin | Father of Io. | M | |
| 590 | Inaki | Latin | Ardent. | M | |
| 591 | Ince | Latin | Innocent. | M | |
| 592 | Inek | Latin | Small. | M | |
| 593 | Inigo | Latin | Fiery. St. Ignacius of Loyola was founder of the Catholic Jesuit order. | M | |
| 594 | Innocent | Latin | Innocent. | M | |
| 595 | Innocenty | Latin | Innocent. | M | |
| 596 | Inuus | Latin | God of fertility. | M | |
| 597 | Iphicles | Latin | Twin of Hercules. | M | |
| 598 | Iphis | Latin | Lover who hanged himself. | M | |
| 599 | Iphitus | Latin | Brother of Iole. | M | |
| 600 | Iris | Latin | Diminutive of Beatrice F: A variant of Beatrix meaning bringer of joy. In the Divine Comedy, Beatrice was Dante's guide through Paradise, perhaps inspired by Beatrice Portinari who was Dante's earliest love. | M | |