Derian le Breton is a moneyer living in Paris in the 1340s. He is very active in the Midrealm and Inter-kingdom moneyers' guilds.
He is also interested in 15th and 16th century martial arts, primarily Italian. Especially Fiore, the Dardi school, and some ~1600 rapier sources.
Derian has lived in several kingdoms: An Tir -> Midrealm -> An Tir -> Caid -> Northshield -> Midrealm. Due to this, he finds inter-kingdom anthropology fascinating.
More stuff at: http://www.erminesable.com