The Windrush scandal, which broke in April 2018, saw the UK government apologise for deportation threats made to Commonwealth citizens' children.
Despite living and working in the UK for decades, many were told they were there illegally because of a lack of official paperwork.
Since then, reports and compensation schemes have been launched, but some people are concerned that not enough has been done.
Who are the Windrush generation?
People arriving in the UK between 1948 and 1971 from Caribbean countries have been labelled the Windrush generation.
It refers to the ship MV Empire Windrush, which docked in Tilbury on 22 June 1948, bringing workers from Jamaica, Trinidad and Tobago and other islands, to help fill post-war UK labour shortages.
The ship carried 492 passengers - many of them children.
It is unclear how many people belong to the Windrush generation, but they are thought to be in their thousands.
They are among more than 500,000 UK residents who were born in a Commonwealth country and arrived before 1971, according to University of Oxford estimates.
The influx ended with the 1971 Immigration Act, when Commonwealth citizens already living in the UK were given indefinite leave to remain.
After this, a British passport holder born overseas could only settle in the UK with both a work permit and proof of a parent or grandparent being born in the UK.
Where are they now?
Many of the arrivals became manual workers, cleaners, drivers and nurses - and some broke new ground in representing black Britons in society.
Jamaican-British campaigner Sam Beaver King, who died in 2016 aged 90, arrived at Tilbury in his 20s and became a postman.
Later he was the first black Mayor of Southwark in London.
Labour MP David Lammy, whose parents arrived in the UK from Guyana, describes himself as a "proud son of the Windrush".
I am campaigning for an amnesty but in reality it would not be an amnesty because that word implies wrongdoing. These people have done nothing wrong. Govt must simply do the right thing, establish a humane route to clarifying their status in this country & change burden of proof.— David Lammy (@DavidLammy) April 16, 2018
Are they here legally?
The Home Office kept no record of those granted leave to remain and issued no paperwork - making it is difficult for Windrush arrivals to prove their legal status.
In 2010, it destroyed landing cards belonging to Windrush migrants.
Because they came from British colonies that were not independent, they believed they were British citizens.
What were they facing?
Those who lacked documents were told they needed evidence to continue working, get NHS treatment, or even to remain in the UK.
Changes to immigration law by successive governments left people fearful about their status.
A review of historical cases found that at least 83 individuals who had arrived before 1973 had been removed from the country.
What did the government do?
Then prime minister Theresa May apologised for their treatment. An inquiry was announced and a compensation scheme established.
The inquiry, which released its report in March 2020, said that the scandal was "foreseeable and avoidable". Its report criticised "a culture of disbelief and carelessness" in the Home Office.
The inquiry made 30 recommendations including :
- setting up a full Home Office review of the UK's "hostile environment" immigration policy
- appointing a migrants commissioner
- establishing a race advisory board
The government has said it accepts the recommendations in full and is working on a plan to implement them.
The Windrush Compensation Scheme was established in April 2019. By the end of March 2020, 1,275 had applied for financial compensation, with 60 people receiving payments totalling £363,000.
About 15,000 claims are expected to be lodged, worth an estimated £200m, before the April 2023 application deadline.
A separate taskforce was established to give individuals correct documentation, with more than 12,000 receiving it or citizenship since April 2018.
How have the government's actions been received?
Inquiry report author, Wendy Williams, has warned there is a "grave risk" of similar failings happening again if the government fails to implement its recommendations.
Campaigners have also criticised the speed at which the compensation scheme has been rolled out, as well as the size of the payments.
For example, an individual would receive £10,000 for being deported, or £500 for denial of access to higher education. Individuals would receive £250 for every month of homelessness.
The government has said that the flat payment for deportation of £10,000 would also be combined with other payments such as loss of earnings. It adds that, including other schemes in place, more than £1m has been handed out to victims.
A campaign to promote the compensation scheme has also been launched.
How is the Windrush celebrated?
Events are held annually to commemorate the Windrush's arrival, and the subsequent wave of immigration from Caribbean countries.
Windrush Day is commemorated on 22 June - the first being observed in 2018. The lead-up to the event is marked with exhibitions, church services and cultural events.
A model of the MV Empire Windrush, featured in the London 2012 Olympics' opening ceremony, while in 2019, the National Theatre put on a production of Andrea Levy's Small Island, a story of first-generation Jamaican immigrants.
In June 2020, the BBC broadcast a feature-length drama inspired by the Windrush scandal.