The troopship SS Mendi sank after a collision on 21 February 1917, claiming the lives of more than 600 South Africans in one of the worst First World War disasters in English coastal waters.
Most of those who perished were black South African troops, nearing the end of their voyage from Cape Town to support the Allied war effort.
In thick fog during the early hours, the Mendi was struck by a much larger cargo ship, SS Darro, off the Isle of Wight, sinking within 25 minutes.
The Darro failed to assist but an escorting Royal Navy destroyer went to the rescue, picking up about 100 survivors.
SS Mendi was carrying the last contingent of the South African Native Labour Corps being sent to meet the demand for manpower on the Western Front.
But the men were not allowed to be armed. Instead, their task would be to dig the trenches, and build the camps, roads and railways for the armies massed in France.
Almost 600 of the men lost on SS Mendi are commemorated in Hollybrook Cemetery, Southampton, at the CWGC memorial to members of Commonwealth land and air forces who have no known grave. This photo shows part of the memorial, which was inaugurated in 1930 (Centenary News)
The disaster claimed nearly 650 lives, including 30 crew members from the Mendi.
Speaking at South Africa's centenary commemorations in Southampton on 20 February 2017, Vice-Admiral Sir Tim Laurence, Vice-Chairman of the Commonwealth War Graves Commission, reflected on the tragic events.
"Those of us who have spent many years at sea can perhaps imagine better than most the panic and confusion caused by the accidental collision of two merchant ships at night - the freezing cold temperatures, the thick fog which disorientated both the survivors of the collision and their rescuers, the threat of attack by enemy submarines.
"All this would have been bad enough for experienced sailors but for men of the land, as most of these men were, it must have been particularly terrifying, an appalling way for the long sea voyage from South Africa to end."
There are many accounts of bravery as the SS Mendi went down.
The Reverend Isaac Wauchope Dyobha, a chaplain accompanying the troops, rallied them with these words: "Be quiet and calm, my countrymen, for what is taking place is exactly what you came to do. You are going to die, but that is what you came to do."
South African and British warships are marking today's Centenary with a wreath-laying ceremony at the SS Mendi wreck site in the English Channel. Tributes are also being held across South Africa - while in the UK, there've been several ceremonies at memorials on the south coast, led by the South African High Commission with support from the Commonwealth War Graves Commission and the Royal Navy. Princess Anne joined descendants and South African representatives for the service at Hollybrook Cemetery on February 20 - Centenary News reports from the Southampton commemorations.
Images: Centenary News
Posted by: CN Editorial Team