More than 1,000 people were killed in four nights in April and May 1941 in German air attacks that came to be known as the Belfast blitz.
Most of those deaths happened in one of those four nights, just after Easter.
Yet this was not a particularly unusual event when considered in the Second World War, such was the staggering scale of that conflict in which up to 60 million people died.
It was, however, an utterly unusual and terrible event in the history of Belfast.
Now Dr Brian Barton has written a detailed account of the blitz on Northern Ireland’s capital city. It is an important piece of history, and has taken him seven years to complete.
This is the last time that such a book could be written using eye witness accounts (eighty of whom he has interviewed). For anyone to have a serious memory of the attack, they would need to have been a child aged around 10 or more at the time. That means they would, at the very youngest, be aged well into their 80s today.
The attack was deeply shocking to Northern Ireland, which felt that it was far enough away from continental Europe to be at risk of such an onslaught. The range that planes had, and the difficulty for Germans passing over Great Britain, meant that the Province felt relatively safe.
Dr Barton recalls how the appalling casualty rates of the Easter attack led to around 200,000 people fleeing the city in the following weeks, one reason why the May attacks had lower fatality rates.
The desertion of the city, with people sleeping in fields in the countryside, is an extraordinary illustration of the terror that was caused by the raids, and is hard to imagine in bustling, 21st century Belfast.
Publication of this book is another reason, 70 years after victory in Europe, to remember those who lost their lives, and to give thanks for the peace that the continent enjoys today.