Why the Snake Woman was a man... well, Aztec society was militaristic to the core, and therefore inevitably male-dominated. So yeah, Yolihuani, I guess it is that age old thing that women didn't hold political power apart from being pawns in strategic marriage games! (but without embarking on a digression about the status of Aztec women here, it's worth remembering you have to view this within the context of the times, and they had considerably more social freedom and legal rights than their contemporary European counterparts, such as in education, holding property, the right to divorce etc).

I guess the real question here is not so much why the Snake Woman was not represented by a woman, but why this role had a female title! *lol*. That the Tlatoani/Cihuacoatl division represented the male (external) and a female (internal) principles of the Aztec universe seems the most logical explanantion, but it does start looking a bit oversimplistic when it comes to Tlaecallel - during his Cihuacoatl-ship (?) he was considered to be not only the chief political force but also the military general responsible for both the Triple Alliance's victory in the war against the Tepanec in 1429, and the expansion of the Aztec empire eastward to the Gulf and southward through Oaxaca to the Pacific.

Although all the references to the position of Cihuacoatl I've found imply there were successive holders of the title, I've not been able to find any names or information on any other Cihuacocoah apart from Tlacaellel. It makes one wonder if it was he was the only one who ever carried real authority within the role? - longevity may have had something to do with (he was active well into his late 80's) and certainly he seems to have been a very able politician and remarkable (not sure that's the right word! *g*) character. Apart from being Cihuacoatl he was also a member of the royal house who was considered at one time to sit on the throne - his contemptuous response to his rejection was apparently, "I am the ruler and you have regarded me as such. How can I be still more of a ruler?" Obviously he had a very definate idea about where the real power lay! *g*. It's said it was Tlacaellel who instigated Itzcoatl's burning of records to obliterate the Aztecs' humilating Tepanec history, and arranged the so-called Wars of Flowers which had the unstated purpose of maintaining Tenochtitlan's military domination over neighbouring states.

After Tlacaellel died in 1496, things were going downhill for the Aztecs: the last three rulers lacked the caliber of their predecessors and the empire was already weakening before Cortes set foot on shore. The Spanish chroniclers understood the Huey Tlatoani to be the monarch, which suggests the role of the Cihuacoatl really didn't seen to be worth a lot by then....