He had hundreds of tenants in Argyll - and more than 2,000 slaves in Jamaica.
Malcolm 12th of Poltalloch, whose family lands stretched through the Kilmartin area of Argyll, made vast riches in both Scotland, Australia and the Caribbean where he owned some 10 large-scale sugar plantations.
Research by British Slave Legacies at University College of London found that, following abolition, the laird filed 11 separate compensation claims with the government to seize back the value of his ‘property’.
He was then paid just under £40,000 for his loss of 2,181 slaves - or around £4.8m at today’s values.
Rachel Lang, administrator at the Centre for the Study of the Legacies of British Slave-Ownership at UCL, said Malcolm 12th of Poltalloch was ‘one of the largest-scale slave-owners in Jamaica’.
Ms Lang said there were variable amounts paid for different people depending on a complex classification system.
She added: “For example a skilled boilerman would be assessed at a higher rate of compensation than an unskilled agricultural worker, the very old and the very young were assessed at a much lower sum.
“Also these values varied from one colony to another reflecting the way that the market values of enslaved people varied from one colony to another.”
She added: “Multiple estate-ownership was not uncommon but one individual to own 10 large sugar estates was very unusual. It’s safe to say he was one of the major large-scale slave-owners.”
According to a paper by historian Professor Allan MacInnes, emiritus professor of history at Strathclyde University, the family’s commercial success was founded on their commodity trading in slaves but also sugar, rum, cotton and cattle.
They were also to heavily profit from advancing credit and mortgages on land to other planters which allowed the family to expand into Tobago, Antigua and even as far as Honduras in Central America, Prof MacInnes added.
When Malcolm 12th of Poltalloch died in 1837, he left a fortune of £500,000 - or some £53m at today’s values.
Professor MacInnes wrote of the large scale evictions undertaken in Argyll by Neill Malcolm, 13th of Poltalloch, a decade after his father’s death.
He said the heir sought to introduce to the Highlands a managerial system that had proved lucrative in Jamaica and their other interests across the Empire.
In doing so, they did away with traditional ties between landlords and tenants and provoked local rioting.
After the spring sowing of crops, Poltalloch, who lived in Hanover Square, Mayfair, took legal steps to remove the tenant farmers and cottars of Arichonan, a community in the Knapdale area.
Tenants resisted attempts by the sheriffs officers, the estate factor and a back-up team of 25 men on the first attempt to remove them from their homes on June 13 1848.
On July 7, the same group returned to Arichonan along with the superintendent of police for Argyll and nine officers.
They planned to remove not only cattle, but also the tenants and cottars and the furnishings from their house.
The encounter was to lead to a number of tenants being imprisoned in the local pub.
Prof MacInnes wrote: “They were met by a hostile party of between 60 to 100 people drawn from Arichonan and neighbouring communities, armed with sticks and stones.
“Having taken one of the ringleaders prisoner, the police and the rest of the eviction party retreated over two miles to Bellanoch where four more protesters were arrested and impounded in the village inn.”
“However, the mob having increased to around two hundred, the police deemed it prudent to release
their prisoners into the custody of trustworthy tenants.”
An attempt to bring in the military to try and push through the eviction was rebuffed by the Crown Office
Instead, it recommended the sheriff-depute and the factor should explain their reasons for seeking a removal that “created such unusual disturbances among a hitherto well behaved and orderly rural population,” MacInnes wrote.
A Gaelic-speaking legal interpreter led to the peaceable removal of the Arichonan community by August 7, he added.
A decade after the evictions, Neill Malcolm, 13th of Poltalloch, who served as MP for Boston from 1826 to 1831, built Poltalloch House, a two-storey, extensive Jacobean-style country house arranged around a central courtyard
The house offered office accommodation, hospitality for business clients and a managerial focus for power-brokers operating on a multi-national scale.”
Designed by favoured society architect William Burn, the Kilmartin pile which cost some £100,000 to build when the project started in 1849 - around £10m in today’s values.
Today, the house is a roofless, abandoned shell where trees have taken root in the rooms once frequented by the wealthy and the influential.