Sorry, in the Journals.
Connacht was the emperor of all human lands during the Wolf Age. it wasn't until the end of the Wolf Age that the Province split off (Possibly during the 20 Years war.)
Lets be honest Connacht is the biggy when it comes to heroes, Destroyed the Myrkridia, defeated the Trow, defeated Mjarin and Moagim.
but besides the fact that he's the biggy we have no proof that he's the statue.
we also knew of Mazzarin in TFl and it looks alot more like a mage than a warrior. Perhaps the book is the Codex and 'Book of Lanreb'is just an in joke that we were never meant to see. Personally I think its Mazzarin.