Maurice Albert Mervyn Davies was born on 21 March 1890 in Adelaide, South Australia, to Laura Esther (née Salom) and Leama Judah (Robert) Davies. Davies was commonly known by his middle name of Mervyn, most likely to distinguish him from his grandfathers. His maternal grandfather, Maurice Salom, was a businessman who had served on the South Australian Legislative Council, while Maurice Coleman Davies, his paternal grandfather, was a notable timber merchant in Western Australia.
In the mid-1890s the family relocated to London, so that Leama Davies could better represent the interests of the family timber company in the United Kingdom. Davies was educated at the Philberds School in Bray, Berkshire, and at Fettes College in Edinburgh. He went up to New College, Oxford, to study arts and law in 1908. Graduating with Honours, Davies was called to the Bar of the Inner Temple in May 1914.
Following the outbreak of the First World War, Davies was commissioned a second lieutenant in the British Army on 17 October 1914. He joined the 9th Battalion of the Devonshire Regiment, with which he went to France in July 1915 for service on the Western Front.
Second Lieutenant Maurice Davies was killed in action on 25 September 1915, during the opening day of the Battle of Loos. He has no known grave and is commemorated on Loos Memorial in Dud Corner Cemetery, Loos-en-Gohelle, Lens, Nord Pas de Calais, France. Davies' cousin, Quartermaster Sergeant Elias Judell, had been killed six weeks earlier while serving with the Australian Imperial Force on Gallipoli.