Otago Anniversary Day in New Zealand Date in the current year: March 24, 2025

Māori settled in the Otago region in the early 14th century. The first European to see the Otago Peninsula was Joseph Banks, an English naturalist on Captain James Cook's first great voyage. He sighted a fire on the peninsula in 1770, which is considered the first indirect contact between Europeans and Māori in Otago.

Over the next decades, Europeans occasionally visited the Otago region, but did not attempt to colonize it until after the signing of the Treaty of Waitangi. In 1844 the New Zealand Company purchased land from the Ngāi Tahu iwi (tribe) and received legal title in 1847. The first settlers were to come from Scotland, so the planned name for the settlement was New Edinburgh. However, the local name Otago (a variant of Ōtākou) was used instead.

The first settlers arrived at Port Chalmers (now the main port of Dunidin) on the John Wickliffe on March 23, 1848. The second ship, the Philip Laing, arrived on April 15 with twice as many passengers. About half of the settlers were members of the Free Church of Scotland, which was one of the original sponsors of the settlement of Otago.

Upon their arrival, the settlers founded Dunedin. The name of the settlement was derived from Dùn Èideann, the Scottish Gaelic name for Edinburgh. During the 1850s, about 12,000 more immigrants arrived in Otago, about 75% of whom were Scottish.

In 1853, New Zealand was divided into six colonial provinces (Auckland, Canterbury, Nelson, New Plymouth, Otago, Wellington) under the New Zealand Constitution Act 1852. Otago occupied the lower third of the South Island, south of the Waitaki River, with Dunedin as its capital.

In March 1861, the Southland Province split from the Otago Province. Two months later, Gabriel Gully discovered gold near the small town of Lawrence in Otago, which led to the Otago Gold Rush and a significant influx of population into the province. After the main gold rush ended, Otago was the most populous province in New Zealand and Dunidin was the largest urban center in the colony.

The Otago Gold Rush brought prosperity to the province of Otago, while the province of Southland began to accumulate debt. By the end of the decade, most Southland settlers wanted to return to Otago. Southland became part of Otago again in 1870. Six years later, however, all provinces were abolished by the Abolition of Provinces Act 1875.

Although the provincial system was short-lived, former colonial provinces still officially celebrate provincial anniversaries to commemorate the arrival of the first colonists or the establishment of the provincial government. These provincial anniversaries are usually celebrated on the Monday closest to the actual date. For example, Otago Anniversary Day is celebrated on the Monday closest to March 23.