Five women who were born in the Democratic Republic of Congo and separated from their mothers by the colonial authorities are suing Belgium for crimes against humanity.
The mixed-race women were taken away from their black mothers on the basis of the colour of their skin.
Belgium controlled the central African country from the 19th Century until it won its independence in 1960.
Millions of Africans died during colonial rule.
At the time, most mixed-race children were not recognised by their fathers and were not allowed to mix with wider society. Thousands were placed into orphanages or other religious institutions where conditions were harsh.
The Belgian state, however, contests whether their plight was a crime against humanity.
The five women were not brought to Belgium when the Republic of the Congo - as it was then known - gained independence in 1960.
Léa, Monique, Simone, Noëlle and Marie-Josée are asking for an initial sum of €50,000 (£42,312; $57,964) in reparations from the former colonial power.
They also want an expert to be nominated to determine further moral damages.
The Belgian state officially apologised for its actions ins the Congo in 2019, with then Prime Minister Charles Michel acknowledging there had been "targeted segregation".
But Monique Bitu Bingi, one of the five women that have gone to court, told the AFP news agency: "We were destroyed. Apologies are easy, but when you do something you have to take responsibility for it."
All five women were born between 1945 and 1950 and taken away from their mothers between the ages of two and four.
And according to legal documents, their fathers refused to recognise the children and the colonial authorities threatened their mothers with reprisals if they refused to let them go.
The case is being examined in Brussels on Thursday, with a potential for further hearings.