Short-lived Germanic kingdom established by Theodoric the Great over Italy and the western Balkans, ended by Justinian's Gothic War of reconquest.
Destroyed by the Byzantine Empire in 552/553 CE at the Battle of Mons Lactarius, where the last Ostrogothic king Teias was defeated and killed by general Narses, ending organised Ostrogothic resistance in Italy.
Detailed study of Ostrogothic history, society, and the Italian kingdom — verified via Open Library.
Contemporary primary source: the official correspondence of the Ostrogothic court of Theodoric and his successors, condensed and translated by Hodgkin (primary source).
Eyewitness/near-contemporary primary account of Justinian's reconquest war that ended the Ostrogothic Kingdom, by the sixth-century Byzantine historian Procopius (primary source).
The migration-era West that this kingdom rose from — broad context for the post-Roman transition.