Rangihaerepō signed the Bay of Plenty (Fedarb) sheet of the Treaty of Waitangi at Ōpōtiki on 27 or 28 May 1840. He asked the trader James Fedarb, who was travelling with the treaty sheet, to mark a cross next to his name to show that he was a Catholic.
Rangihaerepō was among the chiefs who sold the Pākihi block at Ōpōtiki to the Church Missionary Society on 27 January 1840.
By the time Te Aporotanga died in 1866, Rangihaerepō, along with most of the important Te Whakatōhea rangatira (chiefs), had already died.