We are unceratin of Bertie's personal background.
Commonwealth War Graves Commission (CWGC) records state he was the son of Francis and Susannah Mulley, whilst Soldiers Died in the Great War (which can be a dubious source) states he was born at Great Bromley, where he was also living at the time of his enlistment.
There is no record that we have yet found of any Mulley being born in Great Bromley around those dates, or whose birth was registered in Tendring. However there is a Bertie Mulley, whose parents were Francis/ Frank and Susannah who was born at Westleton in Suffolk in 1881/1882. This would also make his age consistent with that held by CWGC. There is no Census record of any Mulley living in Great Bromley between 1880 and 1911, however Bertie Mulley is definitely on the village War Memorial and it is always possible that either he, or his parents, moved to Great Bromley post April 1911.
Bertie volunteered to join the Essex Regiment - most likely at Colchester - on or around 9th September 1914.
We are not totally sure when Bertie was posted to the Regiment's 11th Battalion, but it may have within a few days of joining up as the 11th was what is known as a Kitchener Battalion i.e. one created at the start of the war to XX the influx of recruits who volunteered at that time. From the time of its formation in September 1914, the 11th Essex was billeted in huts on Shoreham Golf Course, on the South coast, though they did spend a few months over the winter of 1914/15 in Brighton.
Certainly Bertie was with the 11th by the time they were sent overseas at the end of August 1915, to join the British Expeditionary Force (B.E.F.), as part of 18th Infantry Brigade, 6th Division. Bertie and most of the Battalion sailed from Folkestone on 30th August, and disembarked at Boulogne that night. The 11th Essex then moved down south where they went into billets in two villages (Estree and Estreeles) just outside the town of Montreuil. There, the Battalion continued with their training continued for the next 3 weeks, in conjunction with the other Battalions in their Brigade and Division.
On 21st September they left the villages, to march to "the Front", which they reached four days later, during the first day of the Battle of Loos. The Battle named after the mining village of Loos-en-Gohelle, near Lens, is now perhaps chiefly remembered for the first use of poison gas by the British
The Battalion's introduction to hostile fire occurred the evening of their arrival at the Front, when they started to advance in stages. Late the following morning, the 26th September, they were ordered to attack the German trenches to their front, just to the south of the village of Hulluch. Despite heavy losses, the Battalion reached the German trenches, and held their position until relieved that night. In their very first action, the 11th Essex had lost 18 officers and 350 men killed, wounded and missing, out of a strength of 29 officers and 942 men.
Bertie Mulley was one of those killed with the Battalion on that day. His body - if recovered at all - was never identified, and he is now officially commemorated by his name being inscribed on Panel 86 of the Loos Memorial. It commemorates over 20,000 officers and men who fell in the area, and who have no known grave.