We do not have detailed information about the geography or politics of the Blackroot Vale region, but Erech was clearly the largest and most important township in this region, and therefore presumably the seat of its lords.

Derufin's name seems to contain the Elvish elements nder-, 'man, adult male' and -fin 'hair', though it's unclear whether this is the intended derivation, or indeed what significance these elements were meant to convey.