On 1 January 2023, Miramichi annexed parts of two local service districts on its northern border;[4][5] revised census information has not been released.

The city of Miramichi was formed in 1995 through the forced amalgamation of two towns, Newcastle and Chatham, and several smaller communities, including Douglastown, Loggieville, and Nelson.

For the Mi'kmaq, Beaubears Island, at the junction of the Northwest and Main Southwest branches of the Miramichi River was a natural meeting point.

On 13 August 1758 French officer Boishebert left Miramichi with 400 soldiers, including Acadians from Port Toulouse, for Fort St George (Thomaston, Maine).

[13][14] In September 1758 Colonel James Murray reported spending two days in Miramichi Bay during the Gulf of St. Lawrence Campaign looking unsuccessfully for Acadians, but destroying anything he found.

[16][17] The French were defeated at Quebec (1759) and Montreal (1760), and the remaining Miramichi settlement was subsequently burned to the ground by British Commodore John Byron (Foul-Weather Jack) in 1760.

Benjamin Marston, a surveyor and the first sheriff, reported in 1785 that "a considerable French Village" had existed on Wilson's Point (adjacent to Beaubear's Island, the present-day site of the Enclosure).

[18] Although they were clearly preceded by the Mi'kmaq and Acadian peoples, credit for the first permanent white settlement at Miramichi is often granted to Scottish settlers, led by William Davidson.

The following month, British Captain Augustus Harvey, in command of HMS Viper, arrived in the area and battled with the Mi’kmaq.

In 1825, a large forest fire, among the worst in recorded history of North America, devastated a number of communities in northern New Brunswick.

Violent outrages were committed in broad daylight, property was stolen and in the worst cases houses and barns were burned to the ground.

[citation needed] Unlike the ports of Quebec, Saint John, St Andrews, Boston, Baltimore, Philadelphia, New York, Charleston and New Orleans, Miramichi did not receive large numbers of destitute and starving Irish during the famine years.

The captain could not get permission to land the sick and dying or to bury the dead for over six days in which further severe anguish and the loss of forty more lives occurred.

Although subsistence farming constituted one part of the new settlement's economy, the thin, acid soils of the Miramichi were not conducive to agriculture; thus, the lumber industry and Atlantic salmon fishery were the mainstays.

A shipbuilding industry was established by Davidson in 1773, largely to facilitate overseas lumber exports, including masts for the British navy, and to provide winter employment for the men.

However, the 1825 Miramichi fire, the advent of steel-hulled ships, and perhaps over-cutting of eastern white pine, would eventually contribute to a long-term decline in the area's economy.

The towns of Newcastle and Chatham developed a long history of rivalry, including a small "war" fought between the communities ("the fighting election of 1843").

The Rankin and Cunard factions literally fought the election in the streets of Newcastle and Chatham with sticks, stones, coal and other missiles.

In 1875, the region's largest construction project in history was completed when the federal government's Intercolonial Railway (ICR) opened between Moncton and Campbellton.

Within a decade, the Canada Eastern Railway was built to link Chatham with Fredericton, along the length of the Southwest Miramichi River valley.

In the 20th century the rivalry between Newcastle and Chatham continued, expressed chiefly through sports, politics, and in competition for businesses and government largesse.

The amalgamation of the former towns and villages to form the City of Miramichi was controversial at the time, and remains so today, due in part to the strong identities that each of the communities possessed.

[24] The Repap paper mill (between the Anderson and Miramichi Bridges) was purchased by UPM in 2000,[25] and was later closed in 2007 because of economic pressures in the North American forest industry and subsequently demolished.

The Plaster Rock – Renous highway (Route 108) offers the quickest connection to major centres in Quebec, Ontario, and points west.

Ocean-going ships entering the port must have a shallow draft, and must navigate the ancient, meandering course of the drowned Miramichi River channel through the inner Bay.

HTI / High Tech Industries owns and operates the marine terminal situated close below the Morrisey Bridge in Miramichi West (the former town of Newcastle).

These roots and the lives of their ancestors provided inspiration for the novels of local author David Adams Richards, the tales and folklore of Herb Curtis, and the fiction and non-fiction books of Chatham writer Raymond Fraser.

About one-half of the sport catch of Atlantic salmon in North America are landed on the Miramichi River and its tributaries[citation needed].

[43] Initially those who died on the island were buried in caskets, but as the death toll continued to rise personal resting places could no longer be an option.

It is the location of many events that take place on the river.The Marine Hospital was built in 1830–1831, and was used to provide care to members of the shipping community involved in the lumber trade.