Yes this is WAD random courtiers are always the same culture as their liege and first names are generated according to culture. For Dynasty names, if you look in the dynasty.txt file in the db folder you see enteries like the following
the province value tells you if a Random courtier generated in the province can take that dynasty name. So dynasty 752, de Normandie, will never be a dynasty name for a random courtier. While dynasty 3121, MacDuff, is a possible dynasty name for courtiers generated in provinces 46 & 48.
Code:
dynasty = {
id = { type = 12 id = 752 }
name = "de Normandie"
province = { }
}
dynasty = {
id = { type = 12 id = 3121 }
name = "MacDuff"
province = { 46 48 }
}the province value tells you if a Random courtier generated in the province can take that dynasty name. So dynasty 752, de Normandie, will never be a dynasty name for a random courtier. While dynasty 3121, MacDuff, is a possible dynasty name for courtiers generated in provinces 46 & 48.