All the children of Marutūahu took part in campaigns to conquer the Hauraki region and districts. Whanaunga and his elder brother Tamaterā were particularly distinguished by their fighting prowess. When Marutūahu died, Tamaterā took on his father’s mantle, overshadowing the rightful heir, his elder brother Tamatepō. This provocative act also brought him into conflict with his younger brother Whanaunga. The differences among the three brothers underlie the development of three separate tribes.
After Tamaterā took on his father’s status, there was such antagonism from his brother Whanaunga that Tamaterā eventually departed, living in several districts including Ōhinemuri, Katikati and Whakatāne. Tamaterā married his mother’s sister, which further strained family relationships. He also obtained certain treasures belonging to his father, Marutūahu.
His people, Ngāti Tamaterā, are a major tribe within the Marutūahu confederation, and their leaders have been prominent in Hauraki history and Marutūahu tribal affairs for many generations. Important early chiefs such as Taharua, Taiuru and Tāwhaki, along with others, have sub-tribes bearing their names. Among the tribe’s 19th-century leaders were Whataangaanga Tūpaea, Tūterangiānini, Tukukino Te Ahiātaewa and Tāraia Ngākuti Te Tumuhuia.
When Tamaterā left, Whanaunga became the dominant brother in the western districts of Hauraki. He and his people, Ngāti Whanaunga, were centrally involved in the conquest of Hauraki lands. They still maintain their presence in the Coromandel Peninsula, on various islands of the Hauraki Gulf, and in the western districts. Key sub-tribes include Ngāti Karaua and Ngāti Pākira. The most well-known 19th-century Ngāti Whanaunga chiefs were Te Horetā Te Taniwha and Hōri Ngākapa Te Whanaunga.
Ngāti Rongoū descend from Marutūahu’s eldest child Tamatepō. The name Rongoū derives from the ancestor Rongomai, a great-grandson of Marutūahu. After Marutūahu’s death, Tametepō’s family faded into obscurity and the line did not achieve prominence until the time of Rongomai. Subsequently Ngāti Rongoū emerged as a tribe. Their name commemorates the establishment (‘ū’ in Māori) of a separate people, perhaps in response to their earlier diminished status.