Amalasuintha

Amalasuintha (495 – 30 April 535) was a ruler of the Ostrogothic Kingdom from 526 to 535. Initially serving as regent for her son Athalaric, she became queen regnant after his premature death. Highly educated, Amalasuintha was praised by both Cassiodorus and Procopius for her wisdom and her ability to speak three languages (Greek, Gothic, and Latin). Her status as an independent female monarch and obvious affinity for Roman culture caused discontent among the Gothic nobles in her court, and she was deposed and killed after six months of sole rule. Eastern Roman Emperor Justinian I used her death as a casus belli to invade Italy, setting off the Gothic War.

Source: Wikipedia — https://en.wikipedia.org/wiki/Amalasuintha