High Quality Content by WIKIPEDIA articles! Waikato is one of the four principal related iwi of the central North island of New Zealand that make up the Tainui waka confederation of New Zealand M ori. This iwi originates from Polynesian migrants who arrived in New Zealand on the Tainui waka, which voyaged across the Pacific Ocean from Hawaiki to Aotearoa (New Zealand) approximately 800 years ago.It is well known that the Waikato iwi has been using the name "Tainui" to describe itself for some time, through the establishment of the Tainui M ori Trust Board in 1946, with many people now referring to the Waikato iwi as "Tainui" or "Waikato-Tainui".