Since ancient times, Gacia has been devided into four provinces ruled by four Great Houses. Each House consists of a ruling family--those of the blood--a clan, and the citizens that live in its borders. Anyone can ask the right to be tried for entrance into the clan, and a test is set by the ruler for each individual. The House Guards must be clan members, so the request is made reasonably often. Clan members earn the right to add 'shi clanname' to their names, roughly translated as 'of clanname.' Members of the ruling family have no family name, using 'di clanname' in place of one. Men and women who marry into the ruling family may choose to keep their family name but cannot pass it on to their children. The head of the House (which may be male or female) is often referred to as 'the di Ranshael' though all members of the ruling family use that suffix.
Examples:
Miaka Jeiman -- given name Miaka, family name Jeiman
Mei Jin Corano shi Ranshael -- given name Mei Jin, family name Corano, of the clan Ranshael
Jen Lai di Ranshael -- given name Jen Lai, of the House Ranshael
The Four Houses:
Ranshael -- The westernmost province, Ranshael's territory is fertile farm land. Its inhabitants are largly farmers and artists, though it also has metalworkers and many of the artisans concentrate on jewelry and armor.
Lencar: East and south of Ranshael, directly south of Sheiling, Lencar is mining country. Rich in mineral deposits as well as jewel mines, Lencar and Ranshael have always been trade partners and allies.
Sheiling: East and north of Ranshael, directly north of Lencar, Sheiling handles manufacturing and processing of materials from Lencar and the other provinces. Prone to bandit attack in old days, Sheiling is also Gacia's primary source for traditional weapons and armor.
Mancara: The westernmost province of Gacia, bordering the coast. Imports and exports have kept the Mancara economy stronger than most over the years, and their fishing industry thrives to this day.