Zachary Macaulay, the third son of the twelve children of John Macaulay (1720–1789), was born on 2nd May 1768. His father was a Church of Scotland minister.
Macaulay only received an elementary education and at fourteen he went to work in a merchant's office in Glasgow. According to his biographer, John Oldfield: "Here, according to an autobiographical fragment which he wrote in 1797, he fell in with a group of university students who undermined his faith and indulged his passion for conversation and debate. Urged on by his colleagues at the counting-house, he also started to drink excessively."
In 1784 Macaulay decided to take up a position as a bookkeeper on a sugar plantation in Jamaica. He was initially upset by the way the slaves were treated but eventually adapted to his new surroundings and by his own account became "callous and indifferent". In 1785 he wrote to a friend: "You would hardly know your friend... were you to view me in a field of canes, amidst perhaps a hundred of the sable race, cursing and bawling while the noise of the whip resounding on their shoulders and the cries of the poor wretches would make you imagine that some unlucky accident had carried you to the doleful shades." Macaulay became a successful employee and eventually he was promoted to under-manager on the plantation.
Macaulay returned to Britain in 1789 and went to stay with his sister Jean, who was married to Thomas Babington, who owned Rothley Temple in Leicestershire. Babington held strong evangelical views and it was not long before Macaulay underwent a conversion. Over the next few months he was introduced to William Wilberforce and Henry Thornton. As a result of his friendship with Babington he was invited to visit Sierra Leone in 1790.
Hugh Thomas, the author of The Slave Trade (1997) has pointed out that "Zachary Macaulay, the indefatigable abolitionist, travelled as a passenger on an English slave ship to discover what such a voyage was like. Macaulay, characteristically, kept his notes in Greek to fool the crew... Macaulay was shown where to sling his hammock and asked if he would not mind a few slaves sleeping under it."
In March 1794 Macaulay became governor of the Sierra Leone Company. The historian, John Oldfield has argued: "A tireless and painstaking administrator, Macaulay steered the colony through a difficult period in its short history. Undeterred by a hostile environment and disputes among the settlers, he opened trade negotiations with the Fula kingdom and in September 1794 successfully resisted an invasion by French revolutionary forces. When he handed over the governorship in 1799 the capital, Freetown, was a bustling settlement of some 1200 inhabitants and the centre of a considerable trade with the interior."
On 26th August 1799 Macaulay married Selina Mills. The couple, who had been introduced by their mutual friend Hannah More, eventually settled in Clapham. Over the next fourteen years Selina gave birth to nine children, five daughters and four sons. This included the historian, Thomas Babington Macaulay. During this period he became involved in the campaign against the slave-trade. In 1804 Macaulay was elected a member of the Society for the Abolition of the Slave Trade, where he worked closely with Thomas Clarkson.
In July, 1807, members of the Society for the Abolition of Slave Trade established the African Institution, an organization that was committed to watch over the execution of the law, seek a ban on the slave trade by foreign powers and to promote the "civilization and happiness" of Africa. The Duke of Gloucester became the first president and members of the committee included Macaulay, Thomas Clarkson, William Wilberforce, Henry Brougham, James Stephen and Granville Sharp.
Wayne Ackerson, the author of The African Institution and the Antislavery Movement in Great Britain (2005) has argued: "The African Institution was a pivotal abolitionist and antislavery group in Britain during the early nineteenth century, and its members included royalty, prominent lawyers, Members of Parliament, and noted reformers such as William Wilberforce, Thomas Clarkson, and Zachary Macaulay. Focusing on the spread of Western civilization to Africa, the abolition of the foreign slave trade, and improving the lives of slaves in British colonies, the group's influence extended far into Britain's diplomatic relations in addition to the government's domestic affairs. The African Institution carried the torch for antislavery reform for twenty years and paved the way for later humanitarian efforts in Great Britain."
Macaulay became secretary of the African Institution. In July 1807 the institution complained about the negative view of Africans promoted by newspapers and books: "The portrait of the negro has seldom been drawn but by the pencil of his oppressor, and he has sat for it in the distorted attitude of slavery. If he be accused of brutal stupidity by one of those prejudiced witnesses, another taxes him with the most refined dissimulation and the most ingenious methods of deceit. If the negroes are represented as base and cowardly, they are in the same volume exhibited as braving death in the most hideous forms... Insensibility and excessive passion, apathy and enthusiasm, want of natural affection, and a fond attachment to their friends... are all ascribed to them by the same inconsistent pens."
In 1814 he travelled to Paris to present the British case for abolition of the slave trade by the continental powers. He also worked closely with the Duke of Wellington and Lord Castlereagh at the Congress of Vienna (1815), where they fought unsuccessfully to block French efforts to revive the slave trade in those parts of Africa where it had already been suppressed."
Macaulay now joined the campaign to end slavery and in 1823 joined with Thomas Clarkson, Joseph Sturge and Thomas Fowell Buxton to form the Society for the Mitigation and Gradual Abolition of Slavery. Macaulay became editor of its newspaper, Anti-Slavery Reporter. He also produced pamphlets such as East and West India Sugar (1823) and Negro Slavery (1824). Macaulay's main task was to provide information to be used by people like Buxton who held seats in the House of Commons.
The abolitionists came under attack when a slave revolt took place in Jamaica. In Parliament William Wilberforce blamed George Canning for passing legislation that abolished the whip on plantations: "Have they given such an order without preparation and without explaining its purpose to the slaves - why it is positive madness!". Macaulay agreed and in a letter to Thomas Fowell Buxton: "You will recollect how I held up my hands in utter astonishment at hearing that ministers had begun their operations by abolishing the whip, by an act, in short, of the most direct interference between master and slave, and that an act of the utmost delicacy and difficulty. The whip... is the grand badge of slavery in the West Indies. Its use is identified with the servile state. Can we wonder that the poor slaves confound this ever-present symbol of slavery with slavery itself, and that they should regard its abolition as but another name for emancipation."
At the conference in May 1830, the Society for the Mitigation and Gradual Abolition of Slavery agreed to drop the words "gradual abolition" from its title. It also agreed to support the plan put forward by Sarah Wedgwood for a new campaign to bring about immediate abolition. The following year the Anti-Slavery Society presented a petition to the House of Commons calling for the "immediate freeing of newborn children of slaves". The Anti-Slavery Society was disbanded after the Abolition of Slavery Act was passed in 1833.