Launcelot St. Vincent Rose was born in Kensington, London on the 4th August 1875. His parents were Frederick William and Kathleen Rose. On the 18th December 1909 he married Agneta Wendela Elizabeth Vann Citters and they had a daughter, Noreen Leonie Rose, born in 1913.

He had joined the Royal Engineers in 1895 and spent time in Gibraltar where he gained a reputation for playing polo, he also spent time big game hunting in Africa.

In September 1914, he returned home and embarked for France in command of 55th Field Company of the Royal Engineers He refused the chance to go home on leave in November 1914 as there was a shortage of officers and was killed in action on the 27th November 1914.

His brother Captain Ronald H W Rose had been killed on the 22nd October 1914.