The Greeks, led by Agamemnon, who had made an agreement between the greek states. They were aided by some of the gods.
Ajax
Not a God. He fought at Troy and is famous from the stories the Odyssey and the Iliad by Homer.
They fought against The Greeks and they lost
the "Battle of Troy" as written in the Iliad as seen in the Film: "TROY". afterward; Odysseus travels back to Greece (the LONG WAY)
The civilization believed to have defeated Troy in Homer's epic poem the Iliad is the Achaean or Greek civilization led by King Agamemnon. They waged the Trojan War against Troy.
Troy
The Iliad is primarily set in Troy and the fields surrounding Troy during the Greek siege of Troy, also known as the War of Troy or the Siege of Troy.
the Greeks
The Cyclops from Greek mythology. Ulysses fought against him in the Iliad.
The Iliad ended with the death of Hector, it never described the sacking of Troy yet.
Ajax
The movie "Troy" wasn't based on a book called Troy. It was based on The Iliad by Homer. The Iliad tells only a small portion of the 10 year Trojan War--about 9 weeks, I believe. The move "Troy" is a condensed version of The Iliad.