Lachlan Macquarie was born on 31 January 1761 on the Isle of Ulva, in the Inner Hebrides, Scotland. His father, Lachlan Macquarie, was a cousin of the sixteenth and last chieftain of the clan MacQuarrie, while Macquarie's mother, Margaret (nee Maclaine) was the only sister of Murdoch Maclaine, 19th Laird of Lochbuy, in Mull. In 1775 the family moved from Ulva to a small farm at Oskamull (near the Ulva ferry crossing) on the Isle of Mull; Lachlan (Snr) died in the autumn of that year when young Lachlan was 13 years of age, while his mother, Margaret, survived until 1810 when she died at Oskamull at the age of 82.

Lachlan (1761- 1824) was one of six brothers: Hector (died January 1778); Donald (1750-1801); and Charles (1771-1835), and two other brothers for whom there are no details except that they were buried at Kilvickewen in Ulva. His only sister Elizabeth, or 'Betty', married Farquhar Maclaine in 1771 and they had three sons and three daughters.

There are few details of Lachlan's early years and education. His army career began in 1776, when at the age of 14 he accompanied his uncle, Murdoch Maclaine (of Lochbuie) to North America as a volunteer. In April 1777 he obtained an ensigncy in the 2nd Battalion of the 84th Regiment (then known as the Royal Highland Emigrants) and performed garrison duty, first in Halifax, Nova Scotia, and later in New York and Charleston. He was commissioned a lieutenant in the 71st Regiment in January 1781 and was posted to Jamaica. In 1784 he returned to Scotland and was reduced to half-pay. Then in 1787, as a lieutenant in the 77th Regiment, he began a long association with India. While in serving India and Ceylon (Sri Lanka) he saw much active service, especially in the south, where he was present at the sieges of Cannanore (1790) and Seringapatam (1791), at Cochin (1795), the capture of Colombo and Point de Galle (1796), the Battle of Seedaseer (1799) and at the second siege of Seringapatam (1799).

On 28 September 1793, he married Jane Jarvis, who was the youngest daughter of Thomas Jarvis, Chief Justice and Member of Council of the Island of Antigua. But their marriage proved to be all too brief - and childless. She died of tuberculosis at Macao, in China, on 15 July 1796 and she was buried in Bombay on 16 January 1797.

In 1801, while serving as Military Secretary to Jonathon Duncan, Governor of Bombay, Macquarie was appointed to the post of deputy-adjutant-general to the 8000-strong army, under the command of Major-General David Baird, that was to be sent to Egypt to defeat Napoleon and expel the French. He was present at the surrender of Alexandria and was able to meet up with his younger brother, Charles, who had received a severe head wound while serving with the 42nd Regiment at the Battle of Aboukir on 8 March 1801. They were able to spend several weeks together, however, on account of this wound, Charles suffered pain and giddiness more or less continuously for the rest of his life. He retired from the army in May 1811.

Macquarie returned to England in 1803 to attend to financial matters, but in 1805 he returned to India where he was promoted to lieutenant-colonel of the 73rd Regiment. After serving in northern India until 1806 he undertook to return to Britain carrying government despatches. After sailing from Bombay to the Persian Gulf, where he narrowly escaped drowning, he then travelled overland to London via Baghdad and St. Petersburg.

However the real reason for his return was to marry his distant cousin Elizabeth Henrietta Campbell, of Airds whom he had met in 1804. He had proposed to her in March 1805 but asked her to keep their engagement secret and wait until his return from India. She had become impatient with his seeming delay, particularly when it became apparent that his tour of duty would be for at least four years. They married on November 3 1807. The bride was 29, and the groom 46. She bore him a daughter, Jane, in September 1808, but unfortunately, the child died on December 4th, the same year.

In April 1809 Macquarie was appointed Governor of New South Wales to replace William Bligh whose governorship had been wracked with controversy. Macquarie and his wife sailed with the 73rd Regiment from Portsmouth in the storeship Dromedary and escorted by H.M.S Hindostan on 22 May 1809, and they arrived at Port Jackson on 28 December. He took up his commission as governor on 1 January 1810.

From the outset, Macquarie saw the colony as a settled community as well as a penal settlement. However, his term of office also coincided with an increase in the number of convicts sent to the colony. His solution was to commence an ambitious programme of public works (new buildings, towns, roads) to help absorb these numbers. He also extended the practice of ticket-of-leave for convicts.

This policy of encouraging convicts and former convicts (emancipists) brought him into conflict with an influential, conservative, section of the local society. This group, known as the "exclusives", sought to restrict civil rights and judicial privileges to itself. Many of these free settlers also had influential friends in English political circles.

Frustration and recurring bouts of illness led him to submit his resignation on several occasions. A serious illness in 1819 almost proved fatal, and the pressures of a Commission of Inquiry into the state of the colony of New South Wales, headed by J.T. Bigge, reinforced his desire to end his term of office and return home to defend the charges made against his administration. Finally at the end of 1820 he learnt that this third application for resignation had been accepted. However, it was not until February 12th, 1822 that he and his wife and son departed for England. (On March 28th, 1814, after six miscarriages, Elizabeth had given birth to a son named Lachlan).

In 1822-23, worried about Elizabeth's health, he took her and Lachlan, with servants and a tutor on a grand tour through France, Italy and Switzerland. Finally, in January 1824 Macquarie retired to his estate in Mull. However, a number of matters still remained to be resolved with the government and in April 1824 he went to London to secure the pension that he had been promised. Unfortunately, while he was there he suffered a recurrence of the bowel disorder that was a legacy of his service in India. Elizabeth hurried down from Mull with Lachlan Jnr. and they were able to reach London in time to see him before he died at 49 Duke Street, St. James on July 1st 1824.