Moriori Educational Resources
Nunuku-whenua, the high ranking Moriori chief of the Hamata tribe, who established “Nunuku’s Law,” which forbade war, cannibalism or killing, in any form.
The law was strictly abided by, and peace was maintained across Rekohu until the islands were invaded by Ngati Mutunga and the Ngati Tama, in 1835. The invaders had guns and they massacred the peaceful Moriori.
http://education-resources.co.nz/moriori/team/nunuku-whenua/