The TUC is urging the government to recognise 23 August as a remembrance day for the abolition of slavery.
The UN already recognises 23 August as a significant date
The date commemorates the 1791 San Domingo (Haiti) revolt, which marked the first decisive victory of slaves against their oppressors.
Unesco, the United Nations' cultural organisation, recognises the date as International Day for the Remembrance of the Slave Trade and its Abolition.
The TUC wants the government to also recognise this "important day".
The government says it supports the commemoration of the abolition slavery.
However, there are no plans for 23 August to become an official day of remembrance.
The date will see Fiona Mactaggart, Home Office Minister for Race Equality, launch a week-long programme of commemorative events.
She said: "Slavery and the slave trade represent a tragic chapter in history and one of the worst examples of man's inhumanity to man.
"Exploring this history can help us meet the challenge of building strong, active and empowered communities in Britain today".
Among remembrance events being held around the world, the UN is leading celebrations in Paris, while a new slavery museum is to open in the US state of Ohio.
In the UK, learning organisation Rendezvous of Victory (RoV) established the programme of commemorative events launched by Ms Mactaggart.
She added that slavery remains major concern.
Ms Mactaggart said: "In the modern world, slavery and people trafficking is still an issue, and the Government is committed to its eradication in every form.
"We promote the widest possible ratification of international agreements that outlaw slavery".
The TUC in North West England is supporting a Liverpool Slavery Remembrance Initiative.
Several events are being held across the city to promote the project.
TUC Regional Secretary for the North West, Alan Manning, expressed his support for an official day of remembrance.
He said: "We fully support this initiative to remember and recognise the impact of slavery in developing our society, and to celebrate the events that lead to its abolition.
"Calling upon the government to recognise this important day in our history sends out a clear message that racism will not be tolerated."
The Home Office has awarded Rendezvous of Victory £5,000 towards commemorative events between 23 and 29 August.
The programme includes a series of conferences, seminars and workshops.