Ioannes

Ioannes is the Latin form of the personal name John, used in Latin-language texts and inscriptions since antiquity. It derives from the Hebrew Yohanan, meaning "Yahweh is gracious." The form Ioannes appears in classical Latin and in medieval and early modern writings, including biblical translations such as the Vulgate, where John the Apostle, John the Evangelist, and John the Baptist are rendered as Ioannes, Ioannes the Evangelista, and Ioannes Baptista.

In the Christian tradition, Ioannes was a common name among saints, bishops, and scholars, reflecting the prominence of John in Western Christianity. Latin authors and ecclesiastical writers rendered many individuals as Ioannes, a convention later adapted in vernacular languages.

Modern usage varies by language: Latin remains a scholarly or ecclesiastical form; Johannes is standard in German- and Dutch-speaking regions; Giovanni in Italian; João in Portuguese; Juan in Spanish; Jean in French; and Ivan or Ioan in many Slavic and Romanian contexts. In English, the familiar form is John, with Ioannes appearing mainly in historical or religious texts. Diminutives include Jan (Dutch/German), Hans (German), and Johnny or Jon in English.

Overall, Ioannes occupies a classical, ecclesiastical niche as the Latin version of a name with extensive linguistic descendants across Europe.