1208 Troilus, provisional designation 1931 YA, is a heavily tilted, large and dark Jupiter trojan, about 103 kilometers in diameter. It was discovered by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany on 31 December 1931. The minor planet was named after the young Trojan prince Troilus, from Greek mythology. He is the son of King Priam (also see 884 Priamus), who in a medieval legend loved Cressida (see 548 Kressida) and lost her to Diomedes (see 1437 Diomedes). Troilus was killed by Achilles (see 588 Achilles) in the Trojan War.