ANTIOCHUS II. THEOS (262-247 B.C.), made peace with Egypt by his marriage with the daughter of Ptolemy Philadelphus, but was tyrannical and unpopular with his people. Antiochus III., sur named The Great (223-187 B.c.), and most famous of the line, was a nephew of Antiochus Theos. By wars in the East, in Asia Minor, and against Egypt he extended the Seleucid empire almost to its original bounds. In an invasion of Greece he was, however, disastrously defeated by the Romans at the Pass of Thermopylae and forced to retire into Asia Minor. The Roman army under command of the brothers Scipio crossed the Hellespont and again defeated him at Magnesia, destroying his army. The defeat stripped Antiochus of all his former conquests in Asia Minor.