Nō te 26 o Noema o te tau 1884, ka whānau a Edward (Ned) Pōhau Ellison (Eruera Pōhau Erihana) i Waikanae, kei kō tata mai i Te Ūpoko-o-te-Ika. Ko ia te tamaiti tekau mā tahi o ngā tamariki tekau mā rua a Rāniera (Daniel) Tāheke Erihana, he tangata ahu whenua, rāua ko tana wahine, ko Nani Weller (Hana Wēra rānei). Ko ngā pakeke o Rāniera ko Thomas Ellison, he tangata hopu wēra nō Ingarangi, rāua ko Te Ikairaua (Te Ikaraua rānei), he tamāhine nā Te Whati, he rangatira nō Te Āti Awa. Ko te mahi i puta ai te rongo o Te Whati ki te ao, nāna nei i kite te kōura i te awa o Kimiākau (Shotover River, ko Haehaenui pea te īngoa tawhito o tēnei awa), ā, whai mai i muri i tērā, ko tōna hurihanga hei pou tokomanawa mō te matakite rā, mō Te Whiti. Ko ngā pakeke o Nani, ko Edward Weller rāua ko Nīkuru, he tamāhine tēnei nā Te Mātenga Taiaroa, he rangatira nō Ngāi Tahu; kua tū noa atu i a Weller he teihana hopu wēra ki Ōtākou i te tau 1831. He rōia te tuakana o Eruera a Tāmati (Thomas) Rangiwāhia Erihana, ā, i te tau 1893 ko ia te kāpene mō te tīma whutupaoro tuatahi o Aotearoa.
E nohinohi tonu ana a Eruera Pōhau Erihana, riro ana nā te tuahine o tana matua, nā Harirota rāua ko tana tāne, ko W. H. Eyes ia i taurima. I pakeketia ia i Pūnehu, i te takiwā o Taranaki, i tētahi pāmu paku noa nei, he miraka kau te mahi. I tana taenga atu ki Parihaka, ka tūtaki ia ki a Te Whiti rāua ko Tohu. He kitekite nōna i te nui o ngā tūpāpaku e hipa atu ana i tā rātau pāmu, ki tōna whakaaro tonu ko te nuinga o aua mate rā he mate tohunga. Ā, koirā te take taihoa ake ia i whai ai i te mahi tākuta hei oranga mōna. Nō ngā tau pokapū o te tekau tau atu i 1890 i mate ai a Harirota, ka hoki a Eruera ki te taha o ōna mātua ki Waikanae noho ai, ā, nō muri ki Ōtākou kāinga, ki te raenga kūiti o Ōtākou (Otago Peninsula).
I kuraina a Erihana ki ngā kura o Pīhama, o Waikanae me Ōtākou. Whāia, nō te tau 1902, ka haere ia ki te Kāreti o Te Aute. I a ia i reira, nāna te mahi tākaro whutupaoro. Ngangahau ana hoki ia i ngā mahi a te Kotahitanga o ngā Tamariki o Te Aute (Te Aute College Students' Association), ā, ā muri ake nei i ērā a te Rōpū Taitamariki Māori (Young Māori Party). Nō mua kē atu i tana pāpāhitanga i ana whakamātautau i te tau 1904 e āhei ai ia ki te haere ki te whare wānanga, ko tana huringa hei Karaitiana. I mua i tāna whakatatūnga he mahi tākuta te mahi māna, ka haere ia ki te Kāreti o Te Rau Kahikatea (Te Rau Theological College) i Tūranga (Gisborne) ako ai. Nā tana kore e whiwhi moni mai i te kāwanatanga me te kore e kaha hoki o tōna whānau ki te āwhina i a ia, ka kitea e ia he mahi māna i tētahi rōpū rūri i Ōtākou, ā, kātahi anō ia ka hoki ki Te Rau. Hei kanohi ia i tēnei wā mō te tīma hōkī o Tūranganui-a-Kiwa (Poverty Bay), ā, nō te tau 1911 ka uru atu ia ki te tīma whutupaoro Māori o Aotearoa.
I a Erihana i te Whare Wānanga o Ōtākou (University of Otago) i ngā tau 1912–13, e ako ana ia i te mahi pūtaiao, ā, nō te tau 1914 i uru atu ia ki te kura tākuta (Medical School). Heoi anō i mau tonu tōna toa ki ngā mahi tākaro, riro atu ana i ngā tīma whutupaoro, tīma kirikiti o te whare wānanga. Nō te 30 o Hūrae o te tau 1913 i moea e ia a Tini Wīwī Taiaroa i Ōrāriki (Sedgemere), i Ōtautahi (Christchurch). Ko tōna matua, ko Te One (John) Wīwī Taiaroa he rangatira rongonui nō Ngāi Tahu, he toa hoki nō te tīma whutupaoro o Aotearoa i te tau 1884.
Nō te tau 1919, nō te putanga o Erihana i ngā whakamātauranga mō te tohu MB me te ChB, ka whakaīngoatia ia hei tākuta tumuaki mō Niue. E hia kē nei ngā tūranga i whakawhiwhia ki a ia i roto i ngā tau e whā i a ia i reira, arā tonu hoki ko ngā tūranga o te kōmihana ā-rohe, kairīwhi hoki, te kaiwhakawā ā-rohe, te kaiwhakawā o te kōti mō ngā tūpāpaku, te āpiha ā-rohe me te tūnga tiamana anō hoki o te komiti e whakamana ana i te hoko waipiro. Nō te tau 1923 i whakaīngoatia ia hei āpiha rongoā, hei kaiwhakawā ā-rohe hoki mō Wharekauri (Chatham Islands), arā, ko Rēkohu rā te īngoa Moriori.
Ka hoki anō a Erihana ki te Whare Wānanga o Ōtākou i te tau 1925 ki te whai i te mātauranga o runga atu e pā ana ki ngā rongoā o ngā whenua pārūrū. I ōna haerenga ki Hāmoa, ā, i muri i tana taenga atu ki te motu o Makogai i Whītī, ka oti i a ia te tuhi tētahi pepa e pā ana ki te mate nei, ki te ngerengere. Nō te tau i muri mai, te whakaritenga i a ia hei tumuaki mō ngā āpiha rongoā, hei kōmihana kairīwhi ā-rohe atu hoki ki te Kuki Airini. Ohorere ana te aituātanga o te hoa wahine, o Tini i te 18 o Hepetema o te tau 1926, nā te piwa rūmātiki i tāoro ai. Ka mahue ngā tamariki tokotoru, kotahi te mea wahine, tokorua ngā mea tāne. Ko tētahi anō he wahine, nō mua noa atu te matenga.
Nō te tau 1927 i karangatia a Erihana kia hoki ki Aotearoa hei whakakapi i te tūranga o Te Rangi Hīroa (Peter Buck), te tumuaki o te Wāhanga Whai Hauora Māori (Division of Māori Hygiene) i te Tari o te Ora (Department of Health). Mau haere tonu tana mahi mai i te taha o ngā kaihautū Māori pērā i a Tā Apirana Ngata, i puta ai i a ia te tuhi ki roto i te pepa, i Te Toa Takitini, he rārangitanga pānuitanga e whakamārama ana i ngā tikanga mō te whakaora i te mate kōea, arā, te tikotiko toto me te rewharewha (whurū) hoki. Tērā ētahi hui nunui i tū ai ia hei māngai mō te Tari. Nā runga i āna mahi ki te whakaora i taua mate anō i ngā moutere o Te Moananui-a-Kiwa, i tōtika ai te kimi oranga mō te mate taipō i Aotearoa. I te pakarutanga mai o te mate nei i Te Kaha, ahakoa uaua te kite i ahu mai i hea, i tino mōhio tonu a Erihana nō te wai unu kē te mate. E hia kē nei te roa e tirotirohia ana te wai, kātahi anō ka kitea kei te tika tonu tōna whakaaro. Nō tētahi wā anō, he pakarutanga mai nō te taipō piwa i Rotorua, ka tonoa anō a ia hei kaititiro mō te mate nei. Ko tāna i whakarite ai he whakatikatika i ngā momo kai o te tangata, tae atu ki ngā āhuatanga o te parukore i ngā kāinga. Tere tonu te pai ake o te mate nei. I mahi nui anō hoki ia ki te whakatōtika ake i te mahi kohikohi tatauranga a te Tari Tatauranga (Census and Statistics Office) mō te taha hauora Māori.
Nō te 12 o Hūrae 1928 i moe ai a Erihana i a Mere (Mary) Karaka Boyd i Te Whanganui-a-Tara (Wellington); tokoono ā rāua tamariki; tokowhā ngā mea tāne, tokorua ngā mea wāhine.
Nō te whakatūnga anō o Erihana hei āpiha tumuaki, āpiha hauora mō ngā Kuki Airini i te tau 1931, mau ake ana i a ia taua tūranga nei mō ngā tau tekau mā whā. Atu i te tau 1932, noho ake ia hei kōmihana mō te Kōti Matua (High Court) o aua moutere. Ēngari pōkia tonutia ana ia e te nui o te raruraru i te taha hauora, me te kite atu anō i te kaha itiiti o ngā rawa e tika ana ki te whakaora i ngā mate nei. Tērā anō tētahi mate nō taua whenua ake, ko te mate nei, ko te noke parakūkā, ā, riro ana mā tana werowero i te tōpūtanga o te tangata ki te ngira kātahi anō ka pai ake. Tāpiri atu ki tēnā ko te mahi whakatika ake hoki i te taha parukore, he mea āwhina ake e te tahua moni a te kaupapa Rockefeller (Rockefeller Foundation). Nāna anō i whakaara ake tētahi kaupapa toko i te ora mō ngā tamariki, torotoro atu ai ngā nēhi i ngā kāinga tūhāhā. Ka mutu, ka kohangia e ia te Kapu Erihana (Ellison Cup) ki te kāinga i tino pai te manaaki tamariki.
He tangata kōhure a Erihana i te mahi whakahaere, tino kaha anō hoki ōna pūmanawa hei kaihautū. I te tūkinotanga a te haumātakataka i te tauranga waka me te hōhipera o Rarotonga i te tau 1934, i tonoa atu a Tākuta F. W. W. Dawson i Aotearoa nei ki te haere atu hei kaiwhakatikatika i te parekura. Tae rawa atu ia ki Rarotonga, kua mārō kē ngā mahi whakapai, kua whakatuwheratia kētia anō te hōhipera. I tere tonu a Erihana ki te whakahuihui i te hunga mate i te ngerengere, kawea atu ana ki tētahi motu tawhiti noa atu mā runga i te kaipuke o Dawson. Nō tētahi wā anō, kino ana te pakaru mai o te mate kōpukupuku, whakamahia ake ana e ia ētahi whare kura me ētahi whare karakia hoki hei hōhipera, meinga ana ngā kura māhita me ngā mihinare hei kaiwhakahaere. He pāhemohemo noa nō te hunga e tūroro ana i te mahi whakakaukautanga a te tangata whenua ki te wai mātao, te take i haria tonutia atu ai rātou ki ngā hōhipera nei. Nā Erihana anō i takoto ai te kaupapa whakakore i te ngārara nei, i te waeroa, inarā nāna i whakawātea rawa atu ngā kāinga i ngā wai whakaroau; nā te pērātanga kua kore haere te mate pārūrū (filariasis) e ahu mai rā i te timonga waeroa, i ōna momo rango anō hoki.
I te tau 1935, ka whakawhiwhia a Erihana ki te Mētara mō te Tiupiri Hiriwa (Silver Jubilee Medal) o Kīngi Hōri Te Tuarima, ā, nō te tau 1938, i ūhia ia ki te tohu hōnore OBE mō te roa me te kaha ōna e tiaki mai ana i te tangata whenua o Te Moananui-a-Kiwa. I tō rāua hokinga mai ko Mere ki Aotearoa i te tau 1945, ka whakatūria e ia he mahi tākuta anō māna ki Manaia, i te takiwā o Taranaki. I reira, ka hou atu rāua ki roto i ngā rōpū ā-iwi me ngā rōpū tākaro. Nō te tau 1953, ka whakawhiwhia ia ki te Mētara Koroneihana (Coronation Medal) a Kuini Riripeti Te Tuarua. Ka tuku a Erihana i tana tūnga i te tau 1956, noho whakatā ana rāua i Ōtātara (Taradale) i Te Matau-a-Māui (Hawke's Bay). Nō te 9 o Noema i te tau 1963, i mate ai ia ki Ahuriri (Napier). Mahue mai ana a Mere me ngā tamariki tokoiwa a Erihana mai i ana wāhine e rua.
He tangata nui a Eruera Pōhau Erihana, arā, hanga nui ana te tinana tae atu ki te kaha me te tōtika anō o te tangata. Mau tonu te mahara o te tangata ki a ia mō tana aroha ki ngā iwi o Te Moananui-a-Kiwa, me ōna kaha hoki ki te whakahaere i ngā mahi. Kāre hoki e warewaretia te pakari me te pūkeke o tōna hinengaro, auau tonu nei te mārō o tōna āhuatanga. Nā tana taha Māori i māmā ai te titiro, te nuku atu hoki o tana mōhio ki ngā tikanga a ngā iwi o Te Moananui-a-Kiwa. Ahakoa kāore i whai wāhi ia i te haputa o te riri tōrangapū, oti atu ana i a ia te mahi nui ki te tiaki mai i te hauora o te iwi o Poronihia, arā, oti rā ki tā te tangata hāngū, ki tā te tangata whakapakepake.