There were two events in particular that resulted in Rua's resistance. Firstly, Rua was deeply distressed by the government's brutal attacks on the Urewera district after 1862 that were a direct violation of the Treaty. Secondly, and most importantly, a major source of grievance for Rua was the way in which the Government treated Te Kooti and the Tuhoe tribe in 1869. Te Kooti was imprisoned in the Chatham Islands, but after escaping prison he traveled to the Urewera's and became a prophet for the Tuhoe Tribe. The government hounded Te Kooti and in retaliation, Te Kooti killed 50 men, Pakeha and Maori alike. His actions had dire consequences as the government forces implemented a scorched earth policy, making it impossible for the Tuhoe tribe to shelter Te Kooti, and leaving them in a very unstable position. The government's unjust treatment of Maori regarding land as well as Te Kooti and the Tuhoe tribe, as highlighted by the scorched earth policy furthered Rua's antagonism towards Pakeha thus explaining why the Land Wars were a long-term cause of his resistance throughout the First World War. .
Nevertheless, the most significant factor of Rua's resistance in World War One was the political, social and legal decision by the government to introduce land confiscations and the Urewera 1896 Act. The Crown wanted to confiscate Maori land to secure culture and residence in New Zealand, as a reimbursement for the Pakeha soldiers who fought in the New Zealand Wars, to provide for the influx of immigrants coming to New Zealand and also to punish Maori who had fought against the Government during these Land Wars. For these reasons, the 1863 New Zealand Settlement Act, and soon afterward, the Native Land Courts were established, both of which ignored Maori rights. This deeply upset the Tuhoe tribe who had fought tirelessly to put an end to the land confiscations and surveying as brought about by the Native Land Court.