Oxford University was already teaching students before which of these existed?

Teaching at Oxford is documented as far back as around 1096, making it one of the oldest continuously operating centers of learning in the English-speaking world. The Aztec Empire did not exist yet then, its capital Tenochtitlan was not founded until 1325, meaning Oxford had already taught students for more than two centuries before the Aztec civilization began.

Comparing Oxford to the Roman Empire or Ancient Egypt would run the opposite direction, both were long over or already ancient history by 1096, so the genuinely surprising comparison is with the Aztecs, a civilization many assume is far older than it actually was.

This kind of timeline surprise is common with the Aztecs, sometimes lumped together with much older civilizations in the popular imagination, when in reality their empire rose and fell within a relatively narrow window, overlapping with events like the Hundred Years' War in Europe.