Ge'ez
Ge'ez, or Classical Ethiopic, is the ancient South Semitic language of the Ethiopian and Eritrean highlands, first attested in pre-Christian inscriptions of the early Aksumite period around the fourth century. The conversion of King Ezana in the 300s opened its literary age: the Bible was translated, and the Book of Enoch survives complete nowhere else.
Ge'ez remained the realm's official written language into the 1800s. The fourteenth-century Kebra Nagast told of Solomon and the Queen of Sheba, anchoring the Solomonic dynasty's claim to rule. Around 1450 the Fetha Negest was translated into Ge'ez and became the kingdom's law.
Muslim invasions in the 1500s broke this literary florescence, though Ge'ez remained the liturgical tongue of the Ethiopian and Eritrean Orthodox churches and the Beta Israel. Its fidal abugida lived on as the script of Amharic and Tigrinya.