Board Thread:Lore Discussion/@comment-17114085-20140621192532/@comment-24933745-20140622132946

This is from the TES wiki:  "Uriel I promoted lawfulness and furthered the establishment of Imperial organizations"

We can assume from this, he was quite proud of his Imperial heritage. I think there would be a mention if Uriel I was Half-Bosmer, he would have Bosmer features like an extended lifespan.