Marcus Aurelius was an able administrator and ruler, but found himself on the northern borders of the Empire fighting a series of defensive wars against Germanic tribes for most of his 19 year reign. He co-ruled with his adoptive brother Lucius Verus for eight years until the latter's death. He decided that his son, Commodus, would succeed him as emperor. Aurelius built very little in Rome, beginning the Column of Marcus Aurelius that was not completed until long after his death. Aurelius remains one of the great figures of Roman history and is generally considered to be the last in a line of good emperors and the end of his reign is often considered the beginning of the decline of the Roman Empire.