Making the story even more interesting was the clear evidence of ritual human sacrifice. Archaeologists excavating Mound 72, as they labeled it, found the remains of 53 women and one very high status man, as well as the decapitated remains of four men who may have been on the wrong side of some sort of authority. The discovery belied the common belief that American Indians lived in egalitarian communities without the sorts of often brutally maintained hierarchies that defined many other civilizations. Was Cahokia an empire, like the Mesoamerican civilizations to the south? It was too soon to tell, but something spectacular had happened here, and it became clear this was a mystery worth trying to solve.
If you want to understand Cahokia, the first thing you've got to do is climb the 156 steps to the top of Monks Mound. From the flat top of this colossus—with a footprint of 14 acres, it is larger at its base than the Great Pyramid of Khufu, Egypt's largest—you not only get a sense of how much labor went into its construction, but you can also understand why it might have been built in the first place. From here you can survey Cahokia's domain: the vast floodplain known as the American Bottom, stretching from St. Louis to a long line of bluffs three miles east of Cahokia and as far to the north and south as the eye can see. After directing the construction of what would have been the highest geographic feature in the 175-square-mile floodplain, a chief or high priest would have had a bird's-eye view of the land under his sway.
Of course, that scenario presumes we know that Cahokia had such a single leader, which we don't. We don't even know what this place was called—the name Cahokia is borrowed from a tribe that lived nearby in the 1600s—or what the people who lived here called themselves. With no written language, they left behind the same scattering of meager clues that makes understanding prehistoric societies everywhere so challenging. (Pottery's fine and everything, but how much would a foreign culture really learn about us by looking at our dishes?) If deciphering the story of history is contentious, try coming to agreement on the story of prehistory. "You know what they say," says Bill Iseminger, an archaeologist who has worked at Cahokia for 40 years. "Put three archaeologists in a room and you get five opinions."