Nate has been Nate for a very long time. I first wrote about him in November 2009, I think. He was always Nathaniel; didn't have a last name though, because back then he was an orphan brat running wild in the catacombs beneath the Skymetal Library.
This incarnation takes more from his re-imagining as the Catalyst's son in 'A catalyst’s son with unprecedented skill, a bastard princess with a secret that could kill her, and the King’s faithless disinherited brother fight for the dreams their births denied them.' I'll be writing that version for this November, I think. They're not quite the same person - Redux!Nate is Null in a land of Mages and Catalysts, and his mother is a Catalyst Herbalist of some skill, so he's much more 'artisan class' than the very working-class Emillion!Nate. But they share a core personality.