A memorial to 53 Welsh Italians killed when their prison ship was torpedoed has been unveiled.
More than 800 people - the majority internees of Italian descent - died when the Arandora Star sank en route to prison camps in Canada in 1940.
Relatives of those who died have raised money to honour the dead.
The memorial was unveiled at a service to mark the 70th anniversary of the tragedy at St David's Cathedral in Cardiff at 1200 BST on Friday.
Around 500 people, including relatives of the victims, local dignitaries and representatives from Italy and Canada are expected to attend the special mass.
An exhibition is also running at the Cardiff Story museum, Old Library, The Hayes, Cardiff, until Sunday.
In June 1940, as Italy entered World War II, Winston Churchill ordered that all male Italians living in Britain - aged 18 to 70 - should be arrested as they were potential enemies to the state.
Despite many having lived in local communities since the turn of the century - and with many of their sons already fighting for Britain in the war - the men were forcibly removed from their homes by the police and the military and interned.
Following a decision to transport a number of internees to Canada and Australia, the liner Arandora Star left Liverpool for Canada carrying around 1,300 Italian, German and Austrian men.
A former luxury ship, it had been painted grey for the war and had barbed wire around it.
Crucially, it did not have the Red Cross painted on it to indicate it was carrying civilians.
On the morning of 2 July 1940, off the coast of Ireland, the Arandora Star was torpedoed by a German U-boat and sank with the loss of over 800 lives - which included more than 400 Italians who had made their homes in the UK.
The Arandora Star is still a sensitive topic for those who lost husbands, fathers, sons and brothers.
Bruna Chezzi, secretary of the Arandora Star Memorial Fund in Wales, said the group, many of whom had relatives on the ship, believed it was time Wales had a way of commemorating the men.
She said: "For the first time in nearly 70 years, families affected by this tragedy of war, which is partly a tragedy linked to immigration, have felt confident enough to share their memories and sufference with the public, without being ashamed or afraid of misjudgment.
"Thanks to the sensibility and patience of those members of the committee for the Arandora Star Memorial Fund in Wales.
"By showing genuine interest and understanding, and in some cases, sharing similar experiences, it was possible to collect precious memories and insights that would have gone lost otherwise in a few years time."