Although he had beaten back a superior force at Te Roto-a-Tara, Te Pareihe knew that the defence of Heretaunga was unsustainable without the advantage of firearms. He and fellow Ngāti Kahungunu chief Tiakitai forged an alliance with Te Wera Hauraki, a chief from Ngāpuhi who had settled on the Mahia Peninsula. Together, their forces retook Te Roto-a-Tara pā from Ngāi Te Upokoiri, who had occupied the fortress island after Te Pareihe escaped to Porangahau. But when news reached the alliance that a huge coalition of Waikato and Tuwharetoa warriors were amassing to attack Heretaunga, Te Wera agreed to protect Te Pareihe and the Ngāti Kahungunu at his fortress settlement in Māhia. Hence, in late 1823, Te Pareihe led an exodus of Ngāti Kahungunu refugees from Heretaunga to Māhia, setting off from the beach at Waimarama. Some chiefs, such as Kurupo Te Moananui, Te Hapuku, and Tiakitai, remained in Heretaunga, but most joined the exodus. By the late 1830s hostilities had ended and the Ngāti Kahungunu diaspora began returning to Heretaunga.