Mendi was built by Alexander Stephen, Glasgow, in 1905, for the British &  African Steam Navigation Co., part of the Elder Dempster Group. She was 370 feet long, 4,222grt, and operated on the Liverpool to West Africa service. She was chartered in 1916 for use as a troopship, and was sent to Lagos, Nigeria to be adapted. The three cargo holds were converted for troop accommodation; officers used the existing passenger accommodation. On 16th January 1917 SS Mendi sailed from Cape Town en route to Le Havre, in a convoy of four troopships with an escort led by the cruiser HMS Cornwall. Mendi was commanded by Captain Yardley, a very experienced master. The vessel carried a large contingent of the 5th Battalion of the South African Native Labour Corps (SANLC) – some 805 black privates, with 22 white officers and 17 NCOs. There were also 56 military passengers aboard, as well as a crew of 89. Large numbers of the SANLC served in the battlefields of Europe, mainly on  tree felling, land clearing, trench digging, etc. as well working at the docks unloading and loading ships and trains. They were all volunteers.

At 5.00am on 21st February 1917, off the Isle of Wight in the English Channel, Mendi was rammed by Royal Mail’s Darro, 11,484grt, travelling in ballast at high speed through dense fog with no alarms sounding. The impact was so severe that Mendi immediately took on a severe list to starboard, preventing many lifeboats from being launched: she sank some 20 minutes later. In all, some 607 black SANLC privates drowned in the icy waters, as well as nine of the officers and 33 crew. [Records vary on the numbers aboard and of the numbers lost – figures given here are combined from several sources] Darro made no attempt to help in the rescue of the survivors, most of whom were saved by boats launched from HMS Brisk, the escorting destroyer. There are several oral records of the the bravery and dignity of the African men, as they realised they would die. The disaster was one of the worst South African tragedies of the Great War, and was also one of the worst maritime disasters of the 20th century. The master of Darro, Henry Stump, was later censured for the disaster. In 2003 South Africa created its highest civilian honour for bravery, the Order of Mendi.