BBC Scotland news website Highlands and Islands reporter
Inverness Royal Infirmary is now an education institute's headquarters
A hospital and schools were partly funded with the proceeds from the slave trade during what a historian describes as the Highlands' "forgotten past".
Dr David Alston researched the region's links with slavery for a series of lectures in Inverness.
He found the city's old infirmary and academy, along with Fortrose Academy received money from the trade.
Dr Alston said during the 1700s and 1800s Highlanders sought their fortunes in the colonies.
The Highland councillor's investigations grew from researching the historic village of Cromarty on the Black Isle.
Dr Alston was intrigued when he read how Hugh Miller, a geologist and fossil collector who was born and brought up in Cromarty in the 1800s, had sat next to a black pupil in school.
He said: "That led me to look at some of the other schools in the area and there were three black pupils at Inverness Royal Academy around the same time.
"There were also black pupils in Fortrose and I am almost certain there were black pupils in Tain."
They were the children of men who had married slaves, or women known at the time as free coloured, while working on or running sugar plantations in the West and East Indies, said Dr Alston.
He added: "It seemed there was a hidden history and this led to an interest in the involvement of people from this part of Scotland in some of the slave plantations.
"There was a period in the early 1800s where the children from mixed relationships came back for education in Scotland.
"That didn't last very long. As the century went on I think peoples' attitudes towards race changed and became more racist."
The Abolition of the Slave Trade Act was passed on 25 March 1807
It has been estimated that between 1700 and 1810 British merchants transported almost three million Africans across the Atlantic
Among the key abolition figures were William Wilberforce, African writer Olanuah Equiano and former slave Ignatius Sancho, above
Guyana, a former British colony in South America, became the focus of his investigations.
Highlanders were drawn to the country by the promise of getting rich quick.
Dr Alston said the sons of Highland landowners were among those who had the capital to invest in Demerara plantations.
And those who did make their fortunes in turn contributed to public institutions back home.
According to his research - which included looking at the records of landowners - Dr Alston found a number of landmark buildings in the Highlands were constructed with funding from the slave trade.
A third of the capital for the old Inverness Royal Academy in the city's Academy Street came from the West Indies.
Half the cost of Fortrose Academy was generated in India, a quarter in the West Indies while the rest was met by London merchants with interests in sugar, cotton and the slave trade.
However, it was 30 to 40 miles (48-64km) of coastline on a far flung corner of the world that most surprised Dr Alston and provided what he said was a "tangible link" between the Highlands and the slave trade.
The former British colony - the only English-speaking country in South America - became independent in 1966
A third of its population is descended from African slaves, imported by the Dutch to work on sugar plantations
About half are the descendants of indentured Indian agricultural workers brought in by the British after slavery was abolished
He said: "Guyana was on the edge of empire.
"People were involved there because they thought they could make money quickly and it was worth running the risk of death from fever.
"They were bringing new land into cultivation along the coast using the Dutch technology of poldering - building embankments and draining the land.
"There is a section of coast in Guyana where the place names almost replicate those from Inverness to Golspie and Helmsdale.
"It is a bit of our history that has been forgotten.
"The reality is that Scots were very much involved in the British Empire, many originally in the military and that experience saw them become involved in economies of the East and West Indies.
"We have tended to brush that under the carpet and adopted a convenient view that this was something done by Liverpool and Bristol merchants."
Dr Alston is to present his report on Thursday as part of a series of lectures hosted by higher education institution, UHI Millennium Institute, which has its headquarters in the old infirmary.