It was the biggest ever loss of life in the Irish Sea.
Shortly before 9 a.m. on 10 Oct 1918 the R.M.S Leinster left the Carlisle Pier, Kingstown bound for Holyhead. On board were 771 passengers and crew. Nearly 70% of these would lose their life.
The weather was fine leaving Kingstown but rough passage was expected. Just before 10 a.m. and about 16 miles from Kingstown people who were on deck saw a torpedo approaching the port side of the ship, a second torpedo struck the port side where the postal sorting room was located. Some were killed in the sinking. Many died in lifeboats or clinging to flotsam awaiting rescue.
The RMS Leinster was one of four ships operated by the City of Dublin Steam Packet Company as both a mail and passenger service. It was a twin propelled ship with paint camouflage and it was armed. There was a postal sorting office on board, the mail was sent to England by train to Kingstown and sorted on board before arriving at Holyhead and vice versa. Twenty one of the twenty two postal sorters on duty that day were killed.
Remains of some of those lost in the sinking of The Leinster were brought to the Carlisle pier. One boat arrived into the harbour with 109 survivors, the dead were being brought in by every boat.
Two of the dead from Stillorgan were brother and sister.
Letitia Harriet Crawford eldest daughter born 28 Apr 1882 at Birr, Co Offaly living at Stillorgan Cottage, Brewery Road married 2nd Lieut Valentine Hill RFA son of John Hill on 16 Jun 1915 at Stillorgan Church. Her body was never found.
Lieut Sydney George Crawford youngest son born 25 Aug 1897 at Tipperstown, Stillorgan. He originally joined the South Irish Horse in 1914 but was discharged as medically unfit, he then joined the Royal Irish rifles. He saw action in Loos and Hulluch, the battle of the Somme, Passchendaele Ridge, Guillemont and Ginchy. On the
17 Nov 1918, a body was found at Mersehead Kirkbean, it was identified by an army disc "Lieut. S G Crawford C of E. RD. Fus.". Two men found the body at 4pm lying at the high water mark, opposite the farm of Mersehead. The funeral took place on Friday, 22 Nov 1918. He was laid to rest with full military honours but with no near relatives present. A memorial was errected by their parents at
Stillorgan Parish Church in 1920.