According to Wikipedia the rectum itself wasn't even discovered until early in the the first year of the Carter Administration.
"Though known in antiquity and referenced in literature as late as the time of Dante Alighieri, the anus fell into disfavor and for over five hundred years disappeared from popular consciousness...
"Only as a result of the relentless efforts of President Jimmy Carter's younger brother Billy did the orifice finally regain the former prominence and esteem it had historically held and so elevate its status to the level of popular affection with which it considered today."