Gallus, (1) Trebonianus (251-253), a Roman Emperor, who succeeded Decius, and was murdered by his troops. He is remembered for having paid the Goths to leave Rome alone. (2) C. Cornelius, a Roman poet, the friend of Virgil and Ovid. He was born 66 B.C., and committed suicide somewhere about 26 B.C. from chagrin at being banished for maladministration in Egypt. Of four books of elegies upon his mistress, Lyc.oris, only fragments are left.