Short answers, pulled from the story.
Priam was the legendary last king of Troy during the Trojan War and the son of Laomedon. He was the father of fifty sons, including Hector, Paris, and Cassandra, and was killed at around eighty years old during the Sack of Troy by Achilles' son Neoptolemus.
Most scholars trace the name to the Luwian word Pa-ri-a-mu-a, meaning "exceptionally courageous," attested as the name of a man from Zazlippa in Kizzuwatna. A popular folk etymology connects it to the Greek verb priamai, meaning "to buy," giving rise to a story about his sister Hesione ransoming his freedom from Heracles.
Zeus sent the god Hermes to escort Priam into the Greek camp, where Priam pleaded with Achilles to return Hector's body. Priam's direct appeal, invoking the memory of Achilles' own father Peleus, moved Achilles to relent. Achilles granted nine days of peace for Hector's funeral, with a promise that fighting would resume on the twelfth day.
Priam was killed by Neoptolemus, the son of Achilles, during the Sack of Troy. Virgil's Aeneid describes Neoptolemus first killing Priam's son Polites at the altar of Zeus, then dragging Priam to the altar and killing him there. An alternative version depicted on Greek vases shows Neoptolemus clubbing Priam to death with the corpse of his baby grandson Astyanax.
Priam is said to have fathered fifty sons and many daughters with his chief wife Hecuba, daughter of the Phrygian king Dymas, and with many other wives and concubines. His most notable children include Hector, Paris, Helenus, Cassandra, Deiphobus, Troilus, Laodice, Polyxena, Creusa, and Polydorus.
Priam has been portrayed by several actors across screen adaptations. Cedric Hardwicke played him in the film Helen of Troy, Peter O'Toole in Troy, Carlo Tamberlani in The Trojan Horse, John Rhys-Davies in the television series Helen of Troy, and David Threlfall in Troy: Fall of a City.