The very first �red carpet' welcome was probably the one offered by Clytemnestra to Agamemnon on his return from Troy in the Classical Greek play, �Agamemnon', by Aeschylus.
It would probably have been more of a purplish crimson - the colour of the gods - but reddish, nevertheless. Treading on the gods' colour would be a sort of sacrilege, which they would certainly avenge. Clytemnestra wanted to show him up as arrogant and deserving of the death she had planned for him for sacrificing their daughter earlier. So, this very early version of the tradition was not exactly �welcoming' after all!