Ah I see, without looking it up I cant remember Achilles's death at all, only that they found him with an arrow through the heel. Or possibly a poisoned tipped arrow. My point was that there was a more than reasonable fear that Hector, a mere Human, could've killed Achilles in a fair environment, without devine intervention, but because Achilles had it on his side, we'll never know.
Paris shot an arrow (depending on the write it's sometimes poisoned) at Achilles, Apollo guided it to the one place it could do harm.
As for the invulnerability thing, I interpret it as it being possible to wound him elsewhere, but not mortally. You could cut him and it would hurt but he's just going to shrug it off and kill you. The gods of Olympus have been wounded by the weapons of man before (Diomedes drew the blood of Aphrodite, I believe), and in the Olympians' war against giants they couldn't kill the invaders (Heracles had to) but they were certainly capable of laying a beatdown on them. Heracles just had to shoot them with an arrow while they were down.
Gotcha, although I feel its worth pointing out (and here I may be exposing my lack of knowledge) that Achilles being superhuman and only having his heel as a weakness could be considered a myth inside the myth itself. As I remember it, the only proof we have that his heel is the only weak spot is that he was found with an arrow through it, and he took several wounds in the story itself. That and while he was certainly a good fighter, he wasnt necessarily the best, as his Mothers (who was a Goddess or a Nymph, so that could throw my theory out of the window anyway) very reasonable fear of Hector proved, that and coupled with the heel thing mentioned above, there is a good argument to be made for Achilles in the Human bracket.
I am only making this point really because I'd like to see Achilles vs Tristan (as I am not a fan of the later additions of Lancelot or Galahad) next year.
Achilles was almost certainly not there during the real Trojan War. It makes more sense to me that he, and the myth surrounding his ankle came about to represent the flaws in the Greek armour at the time of the Trojan War. And he was certainly the best warrior on the Greeks' side (give or take Odysseus the trickster). When he returned to battle after Patroclus' death he killed so many people that he
got into a fight with a river god because he was choking the river with the amount of blood that was getting into it. It then took Zeus to calm him down so that he wouldn't burn troy to the ground before it was fated to. Also when Hector, champion of Troy came face to face with Achilles he ran like a little bitch until Athena (in the form of his favourite brother) persuaded him to man up. His ass was royally kicked.
As for Achilles mother Thetis' fearing for his life, that's because Ancient Greeks took prophesy seriously. Achilles was prophesied to A) be greater than his father (caused Zeus and Poseidon to decide they didn't want to fuck his momma after all) B) either live a long life, be remembered by his successors and then be forgotten or live a short life but have his name talked about around the campfire for a hundred generations (he chose the latter, Thetis wanted the former), and C) that the first Greek upon the shores of Troy would be the first to die (she stopped him from being the first. Patroculs was instead). All came true in the end.
Essentially, she knew he was going to die at Troy, and motivated by maternal love she did everything she could to stop or delay the inevitable. She failed.
Other prophesies relevant to the Trojan war was Odysseus taking 10 years to get home and Paris being "a firebrand that will burn Troy to the ground".
Is my nerdism showing?