Source: Michael Doyle Their Name Liveth For Evermore: The Great War Roll of Honour for Leicestershire and Rutland.
He was the son of Arthur Dennis, a brick works machine fitter, born 1863 in Linton, Derbyshire, and his wife Caroline Dennis (nee Whittaker, married in St. George and St. Mary’s Church, Church Gresley, Derbyshire on the 25th December 1885), born 1863 in Church Gresley, Derbyshire. William Leslie was employed as a part time shoe factory worker and was born in the 2nd quarter of 1888 in Castle Gresley, Derbyshire, his siblings were, Alice Ann, an assistant school teacher, born 1886 in Matlock Bath, Derbysshire, George Thomas, born 1889, Alfred Bertrand C., born 1890 and Elsie May, born 1897, the latter three siblings were all born in Castle Gresley, Derbyshire, in March 1901 the family home was at Cossington Road, Sileby, Leicestershire. In April 1911 William was absent from the family home at Cossington Road, Sileby, Leicestershire, residing there was his father, a brick trade worker, his mother and siblings, George, a hosiery trade mechanic and Alice, a hosiery trade embroiderer, William was serving as a Lance Corporal with the 3rd Battalion King’s Royal Rifle Corps and was stationed at Shorncliffe Camp, Kent. William attested into the Army on a Short Service engagement of 9 years with the Colours and 3 years in the Reserve on the 9th January 1905 in Leicester. He gave his place of birth as Castle Gresley, Derbyshire and his age as 18 years. He gave his trade or calling as labourer and confirmed that he was unmarried. He expressed a wish to enlist into the King’s Royal Rifle Corps. He gave his father, Arthur Dennis, his mother Caroline Dennis and younger brother George Dennis, all of Cossington Road, Sileby, Leicestershire, his younger brother Bertrand Dennis of Kibworth, Leicestershire, his sister’s Alice and Elsie Dennis, both of Cossington Road, Sileby, Leicestershire as his next of kin. His medical examination recorded that he was 5 foot 7½ inches in height, weighed 133 pounds and he had a chest measurement of between 35 and 37 inches. His complexion was described as fresh, his hair colour was black and he had green brown eyes. It was noted that he had a mole in his right armpit. He gave his religion as Church of England. He was pronounced fit for Army service on the 9th January 1905. His record of service began when he joined the Depot of the King’s Royal Rifle Corps at Winchester as a Private, service number 6265 on the 9/1/05. Posted to the 2nd Battalion King’s Royal Rifle Corps on the 22/7/05. Awarded 1st Good Conduct Badge on the -/-/-. Posted to Gosport on the 22/9/05. Posted to Colchester on the 3/10/06. Appointed Lance Corporal on the 8/1/08. Awarded 2nd Good Conduct Badge on the 9/1/10. Posted to Shorncliffe on the 1/2/10. Promoted Corporal on the 3/6/11. Posted to the 6th Battalion King’s Royal Rifle Corps on the 27/5/12. His Company Conduct Sheet records that on the 16/11/12 at Woolwich, he committed the offence of “Improper Conduct when Orderly Sergeant” viz. Irregularity in issuing passes to recruits. He was seriously reprimanded by Major Maitland, Rifle Brigade, Commanding Rifle Depot. Posted to the 2nd Battalion King’s Royal Rifle Corps on the 16/12/12. Promoted Lance Sergeant on the 17/4/13. Extended his service to complete 12 years with the Colours on the 23/5/13. Died from natural causes on the 23/10/14. A summary of his service records: Home Service, 9/1/05 – 7/1/07, 1 year 364 days. India, 8/1/07 – 1/2/10, 3 years 25 days. Home Service, 2/2/10 - -/-/-, 4 years 195 days. British expeditionary Force, France, -/-/- - 23/10/14, 73 days. Total service, 9years 288 days. The following information was provided by William’s father on the 31st March 1919, and was witnessed and signed by -?-, J.P., County of Leicester, of 75, Regent Road, Leicester on ARMY FORM W. 5080 (Information on deceased soldier’s family) Father of soldier, Arthur Dennis of 117, Cossington Road, Sileby, Loughborough. Mother of soldier, Caroline Dennis of 117, Cossington Road, Sileby, Loughborough. Full blood brothers of soldier, A. B. C. Dennis, age 27 of 5, Cal-?- Street, Nottingham. Full blood sisters of soldier, A. A. Burton, age 32 of Whitnall -?-, Mansfield. E. M. McPherson, age 22 of 121, -?- Drive, Peterborough. William’s surviving service documents are in a very poor condition, and much of the finer detail relating to the period of time that he spent in the army, is either illegible or missing, hence the sparse overall description of his military and personal family history.
On Friday December 11th 1914 The Melton Mowbray Times & Vale of Belvoir Gazette published the following article under the heading. “DISTRICT WAR ITEMS.” – SILEBY’S ROLL OF HONOUR. - A WORTHY RECORD. – It is estimated that between 80 and 100 men from Sileby are serving in various regiments at the front or in the fleet, and the following is a list of those who have already either fallen or have been wounded, or made prisoners:- Private A. Freer, Highland Light Infantry, died from wounds, and buried with military honours at Versailles, on September 30. He was a reservist and leaves a widow at Sileby. Private W. H. Meadows, 2nd Grenadier Guards, killed in action and buried at Rond de la Reine. He was a reservist, and leaves a widow and one child at Sileby. Private E. Riddle, 10th Hussars, wounded. Private Hollings, 1st Leicester Regiment, has been unofficially reported killed. His parents are unable to obtain any information concerning him, and have not heard from him for five weeks. Sergeant Dennis King, (sic) King’s Royal Rifles, died suddenly of heart disease in France. Private A. Widdowson, 3rd Coldstream Guards, reported dangerously wounded on the 14th September. Since that date his friends have been unable to obtain any information concerning him. Private B. Riddle, (brother of E. Riddle). K.R.R., wounded in the foot. Private Shuttlewood, Leicester Regiment, severely wounded, and in hospital at Boulogne. Private A. Sharp, K.R.R., and Private J. Dakin, Leicester Regiment, prisoners of war in Gottingen.
On Friday December 24th 1914 The Melton Mowbray Times & Vale of Belvoir Gazette published the following article under the heading. “ DISTRICT WAR ITEMS.” – SILEBY SERGEANT’S DIARY. – GERMAN TREACHERY. – An interesting diary has been kept by Sergeant Leslie Dennis, of the King’s Royal Rifles, whose parents live at Belvedere, Cossington Road, Sileby. Dennis served at the front during the earlier stages of the war, and was found dead from heart failure. The diary records the cordial way British troops were received on their arrival in France. “The French girls did not mind the soldiers kissing them” the writer naively remarks. “They took our cap badges and buttons as souvenirs.” Then he goes on to pay tribute to the splendid behaviour of the troops, who at the beginning of August appear to have been downhearted because they had to do so much marching, and did not get a chance to have a shot at the Germans. Later on he describes “dreadful damage” done by artillery fire. On the 12th, he says. “We had no rations issued today, so we are feeding on carrots and mealies. The place where we are now shows signs of a hasty retreat of the Germans. Every village we come to is absolutely ransacked.” A page or two further on he describes an action thus: “We got up at two a.m., and moved at three o’ clock. We marched one mile when the firing commenced above us on a hill. We moved up the hill, and three or four sections of No.1 Platoon of A Company went as first line, 1 and 2 being in support of them, and myself being with 1 and 2. Sections 2 and 3 had hardly got in touch with the enemy when they retired. Why, I cannot tell. When we got under cover the commanding officer ordered me to advance again with what men I could get hold of. I took these men forward, and got under fire. We lay down and I found we were only about 50 yards from the Germans. The way my fellows were falling was murder. I fired at one, and as I came down to load again a bullet hit my bolt handle and damaged my rifle. Captain Cathcart lay dead by my side as I was firing, and Sgt. Smales had his head blown off. The firing went on for a while, then the Germans started to put up their hands as if they were surrendering. Some of our fellows and some of the Sussex went forward to bring them in. When they got up to them they picked up their arms and started firing at us again. We got about 50 of them and two officers. I do not know what made me do it, but I told my section to be still, and so we got out of that lot. “Then the firing ceased for a time, and two or three of my section went forward and helped one or two fellows out of the firing line. Next I saw young Berridge coming towards the wounded, so I and a fellow named Wicks went to fetch him in. Just as we got up to him and were sitting down to see where he was hit. Wicks said, “I am hit,” and fell over. I asked Berridge where he was hit, and he told me in the leg. I told him to try and crawl out so that I could bandage Wicks up as best I could. Then we went back together. When I got under cover there were two fellows badly wounded, so I bandaged them up. Just as I had finished we had to retire, so we had to leave them. We went forward again into some trenches and stayed till dark. That was Monday 14th September. We had nearly all our officers killed. I counted nine left out of 21.”

Source: Leicestershire War Memorials Project.
The following was kindly provided by Andy Murby in 2017:

Article in the Coalville Times, 01/01/1915:

"DEAD MAN’S DIARY

NOTES OF A BRAVE LOUGHBOROUGH SERGEANT

In pathos always is attached to the diary of a soldier who has fallen in action, and, telling of “hairbreadth ‘scrapes in the imminently deadly breach” the record kept by a Loughborough sergeant of the King’s Royal Rifles is the more pathetic because of the modesty with which he writes of his own deeds and actions of self sacrifice.

Sergeant L. Dennis, Coddington Road, Sileby, near Loughborough, was killed in action on October 23rd, and his diary has been forwarded to relatives. Commencing his narrative in August, the dead sergeant graphically describes the progress of our army into Belgium, and his last entry is dated “21/10/14” – two days prior to his death. Dealing with the reception given to the British troops in France, he has enumerated the various gifts showered upon the men, and on September 6th he writes about the French girls “who did not mind the soldiers kissing them,” and the scramble for souvenirs. On the same date there is a reference to food, and the menu appears to have included eggs, rabbits, fowl, potatoes and other vegetables, but on the 12th September, three days later, there is an entry affording a marked contrast to the foregoing. “We have had rations issued today so are feeding on carrots and mealies” – thus writes Sergeant Dennis after being under heavy artillery fire. “We did not retire,” he adds, “but took up a position. We could do nothing, however, but sit tight while the shells were dropping around us.”

“At a place called Bourg,” the sergeant touches upon an exciting brush with the enemy. “When we got under cover, the commanding officer ordered me to advance with what men I could get hold of. I took these men forward and got under fire. We laid down, and I found out we were only 50 yards from the Germans. It was murder the way our fellows were falling.

I fired at one, and as I came down to load again a bullet hit my bolt handle, and damaged my rifle, so I had to get another one. Captain Cathcart lay dead by my side as I was firing, and Sergeant Smales had his head blown off. After the firing had been going on for a while, the Germans started to put their hands up as if they were surrendering, so our fellows and some of the Sussex went forward to bring them in. When they got up to them, they picked up their arms, and started firing again. We got about 50 of them, and two officers. . . . Two or three men of my section went forward to help one or two fellows out of the firing line. Then I saw young Berridge (a Nottingham man) coming towards me, wounded, so a fellow named Dicks and I went forward to help him in. Just as we got up to him, and were getting down to see where he was hit, Dicks said to me, ‘I am hit’ and fell over. I told Berridge to try and crawl out, so that I could bandage Dicks.

I bandaged Dicks up as best I could, and then we both went back together. Two fellows were badly wounded, so I bandaged them up as best I could. One fellow had his leg shattered, and the other had a wound in his stomach. Just as I finished we had to retire, so we had to leave them. We went forward into some trenches and stayed there until dark. That was Monday, September 14th, and we stayed there until Saturday, September 19th. We had nearly all our officers killed.”