The war began after an especially bitter winter in −963 DR left many Iulutiun villages hungry and suffering. In response, a number of them gathered together and formed a large raiding party. They crossed into Angulutiun territory and targeted the large caribou herds those tribes tended. This act started the war, which would result in fifty years of fighting between the two groups of Ulutiuns.
The fighting finally ceased, a treaty was signed, and with this treaty was established the custom of koatulit, in which persons from the opposite tribes were invited to live as guests for an extended time period of feasting and games. Very little fighting has occurred between the two tribes in the thousands of years following.