Not so much a full-fledged civil war as a successful coup d'etat with the possibility of a civil war.
Coordinator Vincent Kurita was assassinated thanks to his clinically crazy eldest son. His younger son Theodore died earlier, trying to breech fortress republic. The daughter, Emi, is in hiding with the Nova Cats but is presumed dead.
The Coordinator is Yori (Sakamoto) Kurita, granddaughter of Franklin Sakamoto, Teddy K's illegitimate son. She's (supposedly) a puppet of the New Samarkand Warlord, Matsuhari Toranaga.