>>27511
Here's the request thread: >>4450
Ask for links there.
As for a brief summary, Odan-Urr was an ancient alien from long ago (long before even KOTOR) born to a species that could live for centuries and dedicated themselves to tradition. While Urr valued the past, he was a thinker whose boundless wisdom drove him to go beyond his planet and eventually join the Jedi Order where he went on to become one of its most famed Jedi masters and quite possibly the most influential, not because of his combat skills (he didn't like violence but he was powerful), but because of his mind and teachings, and his greatest achievement was founding one of the greatest (if not the greatest) repository of knowledge the galaxy has ever known: The Great Jedi Library of Ossus.
Real world wise, he first appeared in 1994 and his story (along with the other jedi comics of this period) helped to set up a shit ton of lore for the jedi.