Just to the north of Oamaru is the substantial Alliance Abattoir at Pukeuri, at a major junction with State Highway 83, the main route into the Waitaki Valley.

Those at the Waitaki River mouth and at Awamoa both date from the Archaic (moa-hunter) phase of Māori culture, when New Zealand's human population clustered along the south-east coast from about AD 1100.

The area also features Classic and Protohistoric sites, from after about AD 1500, at Tamahaerewhenua, Tekorotuaheka, Te Punamaru, Papakaio, and Kakanui.

[5] Māori tradition tells of the ancient people Kahui Tipua building a canoe, Āraiteuru, which sailed from southern New Zealand to the ancestral Polynesian homeland, Hawaiki, to obtain kūmara.

On its return it became waterlogged off the Waitaki River mouth, lost food baskets at Moeraki beach and ended up wrecked at Matakaea (Shag Point) where it turned into Danger Reef.

On 20 February 1770 James Cook in the Endeavour reached a position very close to the Waitaki mouth and "about 3 Miles [5 km] from the shore", according to his journal.

The Creed manuscript, discovered in 2003, records: Some of the [local] people [had been] absent on a feasting expedition to meet a great party from Taumutu, Akaroa, Orawenua [Arowhenua].

The Pākehā, a party from the Matilda (Captain Fowler), under the first mate Robert Brown with two other Europeans and five lascars or Indian seamen, made eight in all, not seven as the manuscript says.

After Te Rauparaha's sack of the large pā (fortified settlement) at Kaiapoi near modern Christchurch in 1831, refugees came south and gained permission to settle at Kakaunui (Kakanui), and the territory between Pukeuri and Waianakarua, including the site of urban Oamaru, became their domain.

The Jason, for example, probably of New London in the United States, Captain Chester, was reported at "Otago Bluff" south of Kakanui, with 2,500 barrels (400 m3) of oil, on 1 December 1839.

On 9 January he recorded "Our path to-day was sometimes along the edge of a low cliff, sometimes along the beach, till we approached Oamaru point, where it turned inland, and crossed a low range of hills, from which we looked over an extensive plain … Towards the afternoon, we ascended a range of hills called Pukeuri, separating this plain from another more extensive.

The sky was so remarkably clear that, from the highest point of the pathway, Moeraki was distinctly in view..." He made a map and placed Oamaru on it.

James Saunders became the first European resident of the district some time before 1850 when he settled to trade among the Māori of the Waitaki River mouth.

With the development of pastoralism and the associated frozen-meat industry having its historical origins in New Zealand just south of the town at Totara, Oamaru flourished.

The locally plentiful limestone (Oamaru stone) lent itself to carving and good designers, such as John Lemon (1828–1890), Thomas Forrester (1838–1907) and his son J.M.

[11] A major factor in the near bankruptcy of the town was the construction of the Oamaru Borough Water Race,[12][clarification needed] an aqueduct completed after three years' work in 1880.

By the early 21st century, "heritage" had become a conspicuous industry and today[update], the number of buildings owned by the Oamaru Whitestone Civic Trust had grown from the original eight to 17.

Oamaru has a comprehensive range of community sporting facilities for rugby, tennis, swimming, netball, cricket, golf, hockey, and bowls.

Other notable people born and educated in Oamaru include Des Wilson, founder of the UK homelessness charity, Shelter; Australian Prime Minister Chris Watson; New Zealand politicians Arnold Nordmeyer and William Steward; Cardinal Thomas Stafford Williams; Sir Malcolm Grant, former president and Provost of University College London and subsequently Chairman of NHS England and Chancellor of the University of York; and notably former All Blacks rugby union captain Richie McCaw.

Another notable sports person is Gary Robertson, who won gold at the 1972 Olympic Games, Munich, Germany in the NZ Rowing 8.

The world first learned of the death of Robert Scott and the members of his team on their return from the ill-fated expedition to the South Pole by way of a cable sent from Oamaru, on 10 February 1913.

Notable students include Charles Brasch (1909–1973) at Waitaki (1923–1926), a poet and patron of artists; Douglas Lilburn (1915–2001), "the elder statesman of New Zealand music"; James Bertram (1910–1993), writer and academic; Denis Blundell, a future Governor-General of New Zealand; and Ian Milner (1911–1991), the Rector's son, a Czech and English scholar falsely accused of spying for Communism.

His father, known as "The Man", died suddenly on 2 December 1944 while speaking at the opening of a stone gateway to Milner Park, Oamaru.

[31] His interest in mountaineering was fostered while on a geography field trip while studying there, ultimately culminating in him summiting Mount Everest in May 2013.

The Victorian precinct in the southern part of Oamaru's main commercial district ranks as one of New Zealand's most impressive streetscapes[34][35] due to the many prominent 19th century buildings constructed from this material.

Dr. Eric Strawson Stubbs and North Otago farmer Mr. Syd Hurst in 1937, was a forerunner of the New Zealand Farm Forestry Association.

Oamaru has its own community television station, "45 South Television", which transmits from Cape Wanbrow on UHF Digital channel 34, and an independent classic rock radio station Real Classic Rock, which has studios based in Thames Street, and transmits from Cape Wanbrow.

A short side track connects Oamaru's historic precinct and a disused quarry at the harbour, with a tourist steam train running on Sundays.

[54] St Kevin's College, Oamaru is a coeducational state-integrated Catholic day and boarding high school[55] with a roll of 476.

Peter F. Hamilton's novel The Dreaming Void (London: Macmillan, 2007; ISBN 978-1-4050-8880-0) refers to "the backwater External World of Oamaru" (page 22).