I whānau pea a Mohi Te Ātahīkoia ki Waimārama i Te Matau-a-Māui (Hawke's Bay) i te tīmatanga o te tekau tau atu i 1840. Ko tōna whaea ko Maata Kōtakitaki, he tamāhine nā te rangatira o Ngāti Whakaiti, nā Tūāhu rāua ko tana wahine, ko Meretuhirangi. I heke iho tōna tipuna a Whakaiti i a Kahungunu, i a Te Aomatarahi o Ngāi Tahu rāua ko Ngāti Ira, me ngā iwi nō mua kē atu i tahuna ai ā rātou ahi ki roto o Te Matau-a-Māui. Ko ngā rohe whenua o ngā hapū matua o Mohi, arā, o Ngāti Whakaiti rāua ko Ngāti Kautere kei te takiwā o Waimārama. I te wā i whānau ia, ko Tiakitai o Ngāti Kurukuru te rangatira nui. He iwi Pākehā nei i Rangiika e taki noho ana ki te tonga o Te Kauae-o-Māui (Cape Kidnappers), he hopu tohorā te mahi. I raro hoki rātou i a Tiakitai e whakaruru ana. E kīia ana he Pōtikī te pāpā o Mohi, he tangata whaiwhai tohorā, ā, ki ngā whakapapa, ko Kupa te īngoa.
I a ia e tino tamariki tonu ana nā Tiakitai a Mohi i whāngai ā mate noa rāua ko tana pāpā ake i te tau 1847. Ka riro a Mohi i tana pāpā tūranga whānau, i a Pāora Whatuira rāua ko tana wahine, ko Kāterina Morurangi o Ngāti Hikawera, o Te Wairarapa. He tungāne a Pāora nō te whaea ake o Mohi, arā, nō Maata. Ka whāngaitia ki Waimārama. I te tau 1849, he tokomaha ngā tāngata o Waimārama i iriiria e te mihingare, e Te Koreneho (William Colenso). Ākuni pea ko Mohi tētahi. I te wā anō i a ia e taiohi ana nā tana tipuna, nā Tūāhu a ia i ako ki ngā tikanga puri me ngā kōrero tīpuna a tōna iwi. I te matenga o Tiakitai ka noho ko Tūāhu te rangatira. Ko te whakaaro o Mohi ā tōna wā te tū ai ko ia tana whakakapi ēngari nō te hokinga mai o Te Teira Tiakitai, te tama a Tiakitai, i Tūranganui-a-Rua (Poverty Bay) i Āperira o te tau 1850, ka kōrerotia atu a ia e Tūāhu kia noho i te tūranga o tōna pāpā nō te mea e tino tamariki tonu ana hoki a Mohi. Koinei te take i noho rīriri ai rāua ko Te Teira ā mate noa.
I te tau 1858 ka haria a Mohi e ōna mātua whāngai ki Ngā-waka-a-Kupe i te taha whakarua o Wairarapa moana. Ka hangaia he whare ki Uweroa, ka toru tau ki reira ka hoki ki Waimārama. Nō te takiwā ki 1860, ka moe a Mohi i a Ema Te Owha, he tamāhine nā Eru Kaimokemoke. Ko te mātāmua o ā rāua tamariki ko Pita Te Atua Te Ātahīkoia Mohi. Tokorima atu anō ngā tamariki o muri iho i a Pita. Nō muri mai ka moe anō a Mohi i a Pukepuke Tangiora o Ngāti Te Mihiroa. Kotahi tā rāua tamaiti, ko Te Ākonga. He wā kua noho a Mohi me tana wahine tuatahi ki tō rāua whare kei te tuapuke i Waipuka (Ocean Beach) i te raki o Waimārama, he wā kua noho me te wahine tuarua i Pakipaki. Nō te tau 1924 ka mate a Ema; nō te 1936 ka mate a Tangiora.
I te tau 1868 me te tau o muri iho, ka uru atu a Mohi ki ngā taua o Ngāti Kahungunu e whaiwhai ana rā i a Te Kooti i Te Urewera me Taupō. I roto ia i te pakanga i Te Pōrere i te 4 o Oketopa o te tau 1869. I reira ka kōkiritia e tō rātou tokoiti te pā, tokorua ngā wāhine i mau i a ia.
Nō te taenga tuatahitanga ki te Kōti Whenua Māori o te kēhi mō ngā poraka whenua o Waimārama, o Ōkaihau me Waipuka i te tau 1868, kitea ake ana ko Mohi tētahi o ngā kaihoatu whenua, ā, ko tōna whaea tētahi i runga i ngā rārangi īngoa e whai pānga ana ki Waimārama. Ēngari nō te tau 1884, ka puta te hiahia o Te Teira Tiakitai ki te roherohe i ngā poraka i runga i tōna mana anō. Ka whakatakotoria e Mohi te mana noho o ōna tīpuna i Waimārama i te taha o ngā tīpuna o Te Teira, ka rere hoki tana whakaputa i a Tūāhu hei rangatira ōrite te mana ki tō Tiakitai. Whakaaetia ana tētahi wāhanga ake o te take a Mohi mā, ka whakawhiwhia tōna iwi ki ētahi whenua i roto i ngā poraka o Waimārama me Waipuka. Nā ngā raruraru e pā ana ki a ia i roto i te Kōti Whenua Māori, ka nui kē atu te uru haere ōna ki ngā kūraruraru tōrangapū, whenua hoki o te wā. I haere ia i te taha o Hēnare Matua ki Whanganui i te tau 1874. I reira ka kōrero a Hēnare kia whakamutua te rīhi me te hoko whenua, ā, kia nekehia atu te tokomaha o ngā mema Māori i roto i te Pāremata. Nō te hokinga mai ka haere a Mohi ki te torotoro i ngā rangatira o Ngāti Hikawera, i a Wī Hikawera rāua ko Hāmuera Tamahau Mahupuku i Te Wairarapa. Nō te tau 1875 rā anō i hoki ai a ia ki Waimārama.
Ka huri ki te tau 1891, ka noho heamana ia mō te Komiti Māori o Heretaunga. I whaikupu ia ki te Kōmihana mō ngā Ture Whenua Māori i Waipāwa i taua tau; ka whakamāramatia e ia ngā hē e pā ana ki ō rātou whenua kua rīhitia e te Pākehā. I te tau 1906 ka rere tana tono ki te pirimia, ki a Te Hētana (Richard Seddon), kia rāhuitia a Waimārama hei whenua oranga mō te hunga kāinga. Nō te tau o muri mai, ka tirohia ngā rīhi e te Kōmihana Whenua Māori a Rāpata Taute (Robert Stout) rāua ko Apirana Ngata. Ka kī atu a Mohi kāore ia e hiahia ki te hoko i ōna pānga.
Nō te tau 1892, te marama o Āperira, ka uru a Mohi ki ngā whakahaere a te Kotahitanga e whakamātau rā ki te whakatū pāremata Māori mana motuhake. Nō taua wā anō i whakaarahia te tāhū o taua kaupapa i Pēwhairangi (Bay of Islands), ka noho ko ia tētahi o ō rātou kaihautū. Riro anō ko ia hei takawaenga, hei waha kōrero mō rātou, ā, kitea ana tōna kaha ki te taupatupatu. Nō te hui a te Kotahitanga i Waipatu i te tau 1893, kitea ana tōna pukumahi. Ko ia te 'pīka', arā, te tumuaki kōrero o te Rūnanga Nui (te whare o raro) o taua Pāremata mō tētahi wā, ā, nā te pirimia tonu, nā Hāmiora Mangakāhia ia i tautapa mō te tūranga heamana. Pōti kētia ana ko Te Keepa Te Rangi-pūawhe. Ka heke iho a Mohi i tana tūranga pīka i runga i te hiahia kia wātea ia ki te whakaputa i ōna whakaaro, ahakoa anō ngā kī atu kia noho tonu.
I te tau 1897 ko ia tētahi o ngā rangatira o te Kotahitanga i haere i te taha o Tamahau Mahupuku ki Pōneke (Wellington) ki te kōrero ki a Te Hētana mō tētahi pitihana ki a Kuini Wikitōria e tono ana kia rāhuitia ngā toenga whenua Māori, ā, kia kore rawa e taea te wāhi, te hoko rānei. Ko te whakautu a Te Hētana, me whakatū he poari whenua Māori. Nō muri mai ka whakahēngia e Mohi te Pire Whakatautau, Whakahaere hoki i ngā Whenua Māori (Native Lands Settlement and Administration Bill) 1898, a Te Hētana. I taua tau anō ka tū ia ki mua i te Komiti mō ngā Mea Māori (Native Affairs Committee). I reira ka whakahuatia e ia te Tiriti o Waitangi, ka kī 20,000 ngā Māori e whakahē ana i te pire a Te Hētana, ā, ka tono kia riro mā ngā Māori anō e whakatau ngā take rīhi i ngā toenga whenua.
I tū te huinga tuawaru o te Pāremata Māori ki Waitangi i Pēwhairangi i te tau 1899. Ka tohua ko Mohi tētahi o ngā kaiwhakahaere tokowhā hei huri i te motu tono āwhina anō i te iwi. Nō taua tau anō ka whakataetae ia hei Mema mō Te Tai Rāwhiti, ā, tauwhawhai ana rāua ko Wī Pere mō te tūnga nei. Kāore i taea e ia. Nō te tau 1900 ka māmā ake tana titiro me tana whakaae ko te Ture Whakahaere Whenua Māori (Māori Lands Administration Act) me te Ture Kaunihera Māori i whakamanatia i runga i ngā kōkiritanga o te pire a Te Hētana i te tau 1898, he whakatau pai mō te āhua ki ngā tono a te iwi Māori kia riro mā rātou anō ō rātou whenua e whakahaere.
I te matenga o Hēnare Tomoana i te tau 1904, ka noho ko ia hei rangatira aporei mō Ngāti Kahungunu. Riro ana nāna i whakahaere te take whakahoki mai i te taitara o Te Whanganui-a-Orotū, arā, te muriwai me te aka o Ahuriri (Napier), me te whenua rāhui o Puketitiri, ki a Ngāti Kahungunu. I te tau 1918 ka whaikupu ia ki te Komiti mō ngā Mea Māori; nō te tau o muri mai, ka takoto tana pitihana ki te kāwanatanga. Ko te hua, ka whakatūria he kōmihana uiui i te tau 1920. Ahakoa kāore i tutuki tana tono, i whakaarahia anō i ngā tau 1945, 1948 me te tau 1988.
Nā Mohi i whakaemi ngā whakapapa katoa o ōna iwi o Waimārama, ka roa, ka tīmata ki te kohikohi i ō Ngāti Kahungunu e noho ana i Te Matau-a-Māui me tua atu. Ka piki tōna rongo whakaemi kōrero o nehe, ā, nō te marama o Hūrae o te tau 1907 ka tonoa mai tana pukapuka e te komiti o Tānenui-a-Rangi; he komiti tēnei nō ngā kaumātua o Te Wairarapa, ā, i whakatūria hei kohikohi i ngā kōrero o nehe me ngā whakapapa o Ngāti Kahungunu. Ka nui kē ngā kōrero i oti i a Mohi te tuhi mō Waimārama puta atu ki Te Matau-a-Māui. 'Ko tēnei kōrero nō Hawaiki rānoa' te īngoa o taua pukapuka. I tātakitia mai ngā kōrero i Hawaiki, ka whai haere i te ara o Tākitimu, ka heke iho ki ngā tahawhenuatanga o Tamatea rāua ko Kahungunu, ā, ka taka iho ki ngā wehewehenga mai o ngā uri o Kahungunu ki Te Matau-a-Māui mai i Tūranganui-a-Rua. Ka kōrerotia e ia ngā hēmanawatanga i waenganui i ngā iwi o Tākitimu me te tangata whenua, ngā tatau pounamu i pai ai te noho tahi, tae noa ki ngā pakanga i waenganui i a Ngāti Te Whatuiāpiti rāua ko Ngāti Kahungunu i korara ai ngā uri ki Te Wairarapa me kō atu. Haere tonu āna kōrero, ka mutu i te wā i uru atu ai ia ki ngā pakanga ki a Te Kooti.
I mate a Mohi Te Ātahīkoia ki Pakipaki i te 30 o Hune i te tau 1928. I tāpukena ki Waimārama. Kei runga i tōna rua ēnei kōrero, 'He kaiārahi nō te iwi'.