Sermones De Ludo Cum Aliis, called the Steele Sermon, designates the card number 4 and calls it La papessa (The Popess.) The sermon dates to late fifteenth century and condemns Tarot for its Christian iconography.
Here's another path to consider:
The Rosenwald Sheet, dated around 1500 CE ascribes numbers identical to modern Major Arcana to the first five images. Although numbering problems surface later in the printing project, the wood-block printed sheet likely provides a good example of typical cards of that time. Obviously, symbols on this sheet like the forbidden image of legendary Pope John the VII, who allegedly served as Pope for a few years until pregnancy exposed her as a cross-dressing female offer the kind of religious symbolism a person tended to hide, not document, in the Middle Ages. Researchers widely believe The High Priestess card depicts legendary Pope Joan. In the Middle Ages, giggling peasants probably whispered the legend of the Popess to retaliate against the oppression of Roman Catholic aristocracy. Renaissance versions of The High Priestess card feature toned-down religious symbolism. Like the torture device shown on The Wheel of Fortune, Pope Joan offers a medieval link.
Rosenwald images of the Pope and Popess bear an uncanny resemblance to each other and the depiction of the Pope appears distinctly feminine. The concept of men and women holding equal religious rank suggest Gnosticism an ancient rival of Catholicism. Gnostic Christianity varies from Church doctrine in that Gnostics allow women equal positioning in religious hierarchy, which enraged the Catholic Church. Pope Innocent III openly labeled Gnosticism as heresy. The Albigensian Crusade from 1209 until 1255 CE represented efforts by the Roman Catholic Church to crush Gnostic Christian sects known as Cathers in Southern France. Having captured the small village of Servian, Crusaders headed for Béziers, arriving on July 21, 1209 CE. Although surrounded, the town refused demands to hand over the Catharists. The town fell the following day. After Crusaders followed a retreating counter-assault into the city, they slaughtered the entire population. Papal representative, Abbot Arnaud-Amaury, apparently declared, "Kill them all! God will recognize His own.” Over ten-thousand died in Béziers, although the town supposedly held around five-hundred Cathers. News of the horrors at Béziers rapidly spread, causing other target settlements to cow-down to the invaders. Cather strongholds progressively fell, the largest at Peyrepertuse in 1240 CE.
A small, isolated fort at Quéribus, appears the final holdout, overlooked until August 1255 CE, when Crusaders took swift action and it fell. Military efforts took a toll on Gnosticism but the real threat emerged as the Inquisition began in 1222 CE. The final Cather burning, by the Inquisition occurred in 1321 CE. No real evidence of European Gnostic practices survived efforts of the Church, which meticulously attempted to destroy all traces of actual beliefs of this rival Christian sect. If Papal officials perceived Tarot as a Gnostic practice, any evidence referring to the cards vanished in the same manner as most Gnostic writings. Gnosis is Greek for wisdom or knowledge but the term came to denote a variety of religions not condoned by the Church.
I can offer no other documented research paths for the Popess at this time. I fear Papal medling in history may impair your research but please keep me abridged of your findings on Pope Joan. I find it fascinating.
