Almost all the cabinet and several junior ministers will attend ceremonies to mark 150 years since the abolition of slavery in the Netherlands on July 1, during which king Willem-Alexander is expected to make a formal apology.

The king and queen Máxima will be at the national Keti Koti ceremony in the Oosterpark in Amsterdam, together with prime minister Mark Rutte and a heavyweight delegation of four ministers, broadcaster NOS said on Tuesday. 

Last week it emerged that the Dutch royal family played an important role in slavery, exploitation and forced labour during the Netherlands’ “golden age”, and earned some €545 million in the process. 

At the end of last year, king Willem-Alexander ordered a complete review of the role of his forebearers and the royal house in colonialism. And in November, it was announced that the royal family’s collection of colonial-era artifacts is to be checked over by experts to make sure none of it was stolen or taken by force.

Dutch colonies

The ending of slavery will also be commemorated in the former Dutch colonies in the Caribbean and South America.

Health minister Ernst Kuipers is representing the government on Curaçao, housing minister Hugo de Jonge will be on Bonaire and foreign minister Wopke Hoekstra in Suriname. Junior ministers will be at similar ceremonies on Sint Maarten, Saba, Sint Eustatius and Aruba.

Rutte formally apologized for the Dutch role in the slave trade in December last year, a controversial event that was criticized by some organisations campaigning for justice.

Slavery was finally abolished in the former colonies of Suriname and the Dutch Antilles on July 1, 1863.

Slavery and the Netherlands: what you need to know

However, slaves in Suriname were only fully freed in 1873, since the law stipulated that there was to be a mandatory 10-year transition period. Owners were also paid compensation of 300 guilders for every enslaved person they released.

At its height in the 1770s, slavery generated over 10% of the gross domestic product of Holland, the richest of the seven Dutch provinces which made up the republic, according to social history researchers.

The income from the tobacco trade, sugar processing and shipbuilding was boosted by the use of slave labour used to grow crops on plantations, according to researchers at the International Institute for Social History.