I can't answer to when the tradition started but I can say that for as long this old memory of mine has been, we always had chiltlins on New Years. Texas, Okla and here in Ariz, all the folks I knew have done this. Can't tell you what the Chitlins were for ( perhaps good eating) but you had to have black-eyed peas for good luck through-out the year, Collards, Turnips or Mustard greens was for money. so that you would not go broke.