The sedes stercoraria [the posterior chair], a heavy, wooden throne with a conspicuous hole in the seat (à la a commode), despite its incredulity-factor, is not a bawdy myth created to poke fun at the gullible. These ‘thrones,’ in early Medieval times did serve a purpose, but contrary to what most believe it was not to check for gender per se! It is said that a there was a sedes stercoraria at St. John’s Lateran during the first part of the second millennium and there are persistent claims that at least two originals have been preserved within the Vatican (at one of the many museums) and in the famed Musée du Louvre in Paris [France]. Pope Joan, on the other hand, is an unmitigated, bold-faced fabrication.
Bluntly stated, there could not have been a ‘Pope Joan’ because there are no unaccountable gaps in papal history, between the ninth and thirteenth centuries, into which she could be slotted into. J.N.D. Kelly, in his bible-like ‘Oxford Dictionary of Popes,’ confirms this, uncategorically, and even states that this myth was demolished by a French protestant in the seventeenth century. On the whole Professor Kelly didn’t make too many errors and if he says that there was no female pope, it really should be taken as gospel. But, if you want additional affirmation please look her up, under ‘Popess Joan,’ in the 1914 Catholic Encyclopedia – another, in the main, oracle-like source. They don’t mince any words or leave anything to doubt, when they say: ‘This alleged popess is a pure figment of the imagination.’ The Wikipedia entry for ‘Pope Joan’ will gives you a good overview and give you access to many a useful link. If it is any consolation, I too, painstakingly, checked papacy dates and interregnums to see if there were any gaps that would provide credence for ‘Joan.’ I also double-checked the bona fides of all 24 of the ‘Johns,’ pope and antipope, to see if any of them, particularly the early ones, could have been a female. Suffice to say I did not find anything. J.N.D. Kelly and the 1914 Catholic Encyclopedia are spot on.
The best I can offer is that ‘Pope Joan’ probably was an inspired and very pointed allegory to the travesty of the so called ‘pornocracy’ [i.e., Saeculum obscurum (dark ages) or even the ‘Rule of the Harlots’], between 904 to 964, when the papacy was but a puppet of the amoral, ruthless, mother-daughter duo of Theodora and Marozia. The legend of ‘Pope Joan’ may have been a feeble, medieval attempt to portray that there was a period in papal history when the pope might as well been a female.
The Sedes Stercoraria Was To Check Against Castration!
Simple as that. So it wasn’t to check for females masquerading as males, but to make sure that males had not been subject to self- or forced castration.
Self-castration by driven, ascetics had always been a problem. Per tradition supposedly dating back to the times of the Old Testament one could not be a priest (as opposed to a monk) if not fully intact.
The First Council of Nicaea, in 325, was the first Ecumenical Council of the Church. It was convened by Emperor Constantine ‘The Great’ I, the liberator of Christianity who even personally attended some of the sessions. It had been convened to resolve the then raging ‘Arian Controversy’ [i.e., the exact nature of the relationship between the Father and the Son vis-à-vis the Trinity]. This seminal council promulgated 20 canons. The first was to prohibit self-castration!
That alone provides us with an unassailable data point as to how serious an issue self-castration was to the Church.
Extreme violence against popes, antipopes, their followers, papabili and Roman clergy, by competing camps or imperial forces was not uncommon well into the second millennium. In 768, after Stephen III (IV) (#95) was elected, antipope Constantine, who had seized the papacy a year earlier had his eyes gouged out by a mob partial to the new pope. Gelasius II (#162), 1118 to 1119, though elderly when elected pope, was twice brutally attacked during his short pontificate. Thus, it was not inconceivable that there could a pope-elect who had suffered irreparable damage during a skirmish.
If it ever came to pass that the pope was not intact it would, at a stroke, discredit the pope and undermine the papacy.
Thus, it would have made sense, in those tumultuous days to make sure that pope-elects were intact – prior to them taking office.
Hence, the Sedes Stercoraria.