There have been many attempts to analyse and explain the reasons why 52% of Britons voted to leave the European Union in June 2016. But while so much about Brexit remains uncertain, one thing does seem clear: concern about immigration had an influence on the result.
As a former immigration minister, I have first-hand experience of just how vexed a political issue it can be. But what has often struck me about so much of the discussion about migration among politicians and in the media is the lack of appreciation of the long story.
Immigration often tends to be presented as a contemporary phenomenon - post-second world war, post-EU expansion or even post-Arab spring. In fact, nothing could be further from the truth. While the pace of movement may have increased in recent years, migration has always been a part of British life.
Similarly, while immigration remains key to the ongoing negotiations between Britain and the EU, Brexit is far from the first potentially pivotal moment in this country's migration story.
No Turning Back: Seven Migration Moments that Changed Britain, a new exhibition from the Migration Museum Project, which I chair, explores seven such turning points through a range of personal stories, commentary, photography and art. Some are relatively well-known, others lesser-explored; some brought people together, others moved people apart; all had a profound effect on individuals who lived through them - and on the nation as a whole.
These moments range from the expulsion of England's entire Jewish population in 1290, to the large increase in the number of people defining themselves as 'mixed-race' in the 2011 Census; the first East India Company voyage to India in 1607, to the Rock Against Racism movement of the late 1970s; the arrival of Huguenot refugees in the late 17th century, to the first peacetime piece of legislation controlling who could - and couldn't - enter the country in 1905, and the first commercial jet flight by the British Overseas Airways Corporation in 1952.
These seven are by no means a definitive chronological list - the number of significant migration moments is as varied and twisting as the story of Britain itself. Instead, they are presented as starting points to enable visitors to explore themes and stories about migration - and to spark conversations about moments that matter to them.
I first made the case for a national migration museum almost 15 years ago, an idea that stemmed from my time at the Home Office, and from visiting similar museums in other parts of the world - notably Ellis Island in New York. I found it strange that Britain, which has one of the best arts and heritage sectors in the world, lacked a cultural space devoted to exploring the integral role that the movement of people to and from these shores has played in the formation of this country as we know it.
Since then, myself and a dedicated team drawn to the project from a diverse range of sectors and backgrounds, have been working to fill this clear gap in Britain's cultural landscape.
We took a major step towards this goal in April, with the opening of the Migration Museum at The Workshop, just across the river from the Houses of Parliament. Until spring 2018, this temporary museum will stage a series of exhibitions and events exploring who we are and where we come from.
No Turning Back is our most ambitious exhibition to date, and encapsulates what the Migration Museum for Britain that we are creating is all about - providing a cultural space for exploration of how immigration and emigration across the ages has shaped who we are today as individuals, and as a nation.
Against the current backdrop of fierce national debate and immense uncertainty, the need for examination of this important theme that connects us all could scarcely be greater.
No Turning Back: Seven Migration Moments that Changed Britain is at the Migration Museum at The Workshop, 26 Lambeth High Street, London SE1 7AG, Wednesday-Sunday 11am-5pm (late opening on the last Thursday of each month) until February 25, 2018. Admission is free. For more information, visit migrationmusuem.org