(Decimus Magnus), a Roman poet of the fourth century, was the son of an eminent physician, and born at Burdigala (Bordeaux) about A.D. 300. His education was conducted with unusual care, either because his genius was very promising, or because the scheme of his nativity, which had been cast by his maternal grandfather, was found to promise great fame and advancement. He made extraordinary progress in classical learning; and after completing his studies at Toulouse, he practised for a time at the bar in his native place. At the age of 30 he became a teacher of grammar, and soon afterwards was promoted to be professor of rhetoric. In this office he acquired so great a reputation that he was appointed preceptor to Gratian, the Emperor Valentinian's son. The rewards and honours conferred on him for the faithful discharge of his duties, prove the truth of Juvenal's maxim,—that when fortune pleases she can raise a man from the humble rank of rhetorician to the dignity of consul. He was appointed consul by the Emperor Gratian in the year 379, after having filled other important offices; for besides the dignity of quæstor, to which he had been nominated by Valentinian, he was made prefect of Latium, of Libya, and of Gaul, after that prince's death. His speech returning thanks to Gratian on his promotion to the consulship, is highly commended. The time of his death is uncertain; but he was certainly alive in 388, and is said to have attained a great age. It has been supposed that he was a convert to Christianity. There is great inequality in his works. His manner and style are often harsh, and he is decidedly inferior to Claudian in Latinity and versification. The best edition of Ausonius' poems is the Variorum of Tollus, published in 8vo at Amsterdam in 1671.