Marcus Aurelius Antoninus Augustus (26 April 121 - 2 July 180) was the Caesar of Rome from 161 until his death in 180 CE. Ruling alongside co-emperor Lucius Verus until his death in 169, Marcus was sole emperor for eleven years of his reign. His rule faced the onslaught of a renewed Parthian Kingdom and dangerous invasions by the Germanic tribes along the frontier. Aside from these struggles, Marcus Aurelius' reign is remembered for being a prosperous period of Imperial Rome, earning him classification as the fourth of the historical Princepes Boni.