Historiarum ab inclinatione Romanorum imperii decades

Historiarum ab inclinatione Romanorum imperii decades (Decades of History from the Deterioration of the Roman Empire) is a significant work by the Renaissance humanist historian Flavio Biondo. Written between 1439 and 1453, this comprehensive history covers Europe and Christendom from the sack of Rome in 410 CE up to 1442.12

Biondo's work is notable for introducing the concept of the decline of the Roman Empire and establishing the idea of the Middle Ages as a distinct historical period spanning from 410 to 1410. He utilized critical textual analysis to refine historical accounts and eliminate legends, providing a chronological framework that bridged ancient Rome and his own time. This meticulous approach influenced later historical notions, including the concept of a thousand-year Middle Ages.12