Roman Asia, also known as Asiana, was a Roman province which existed from 133 BC to the 13th century AD, with Ephesus serving as its capital. Following the disastrous Battle of Magnesia in 190 BC, King Antiochus III of the Seleucids was forced to cede Asia to the Roman Republic, which placed it under the control of its client state of Pergamon. After the death of King Attalus in 133 BC, Pergamon passed under Roman control, and the Romans crushed a revolt by Eumenes III, who sought to perpetuate Pergamese independence. King Mithridates VI of Pontus briefly succeeded in conquering almost all of Anatolia, slaughtering all 150,000 Romans in the province of Asia alone. In 85 BC, Sulla defeated Mithridates and returned the province to Roman control, and, after Augustus came to power as the first Roman emperor in 27 BC, he established a proconsulship for Asia, and he established the province of Galatia. During the 3rd century AD, Asia began to decline due to a plague outbreak, and, in the 4th century AD, Domitian divided Asia into four smaller provinces. It remained a center of Hellenistic culture until it was conquered by the Ottoman Empire at the end of the 13th century.