More than 2,000 people gathered at Westminster Abbey to celebrate the 70th anniversary of the arrival of the Windrush generation in Britain.
Prime minister Theresa May attended the event alongside Home Secretary Sajid Javid, London Mayor Sadiq Khan and shadow home secretary Diane Abbott, as well as Baroness Lawrence, mother of murdered black teenager Stephen Lawrence.
The Empire Windrush landed at Tilbury on 22 June 1948 as people came ot Britain to help rebuild the country following World War II.
Descendants of those who arrived in that era attended the service, which saw gospel choir sang the lively Jesus Hold My Hand and actors recount stories of the Windrush.
The celebrations come following the Windrush scandal which saw the Government wrongly deport and deny people NHS treatment, access to housing and work despite having legal right to be in the country.
Ms Abbott, who has written to Mr Javid, called on the Government to "come clean" about the full extent of the scandal, blamed on the "hostile environment" to immigrants championed by Mrs May when she was in charge at the Home Office.
"Warm words about commemorating the Windrush generation are not enough," the Labour politician said, adding a call for a hardship fund to help support Windrush citizens.
Labour MP David Lammy, whose Tottenham constituents are among those affected, said British-Caribbeans must be celebrated on the day, but warned the scandal had "left a very nasty taste in the mouth".
More than 2,000 people have been provided documentation since April by the dedicated Windrush taskforce, the Home Office said, helping them to demonstrate their right to residence.
Under the new Windrush scheme, which offers free citizenship for Commonwealth citizens who arrived before 1973 and children who joined their parents before they turned 18, some 285 people have so far been granted citizenship, they added.
So far the Home Office has made contact with 11 people who may have been wrongfully removed from the UK as a result of the fiasco