At first, I thought "of course not, we weren't a space-faring race" but after watching "Matters of Honor":
Maybe we did play a role, after all. Speculation about real-world events in the 13th century that might support this are welcome.
G'Kar: They came to our world over a thousand of your years ago --- long before we went to the stars ourselves. They set up a base on one of our southern continents. They took little interest in us. G'Quan believed they were engaged in a war far outside our own world.
Maybe we did play a role, after all. Speculation about real-world events in the 13th century that might support this are welcome.