Leonard Greenhill was born in Hemel Hempstead, Hertfordshire on Tuesday, 30th April 1895, the tenth of eleven children born to William Greenhill and Maria Lucas. The children were: Frederick, Henry, Annie, Charles, Florence Annie, Charlotte Elizabeth, Annie Maria, George William, Walter Sidney, Leonard and Emily. Henry and Annie both died shortly after they were born, Charles died in 1882 aged three and Charlotte Elizabeth died in 1886 aged twelve. His brother’s George and Walter both served in the Great War with the Royal Artillery and the Essex Regiment respectively. Both survived the conflict.

Leonard grew up in Chaulden, Hemel Hempstead, where his father William was a "Cattleman" and when he started school in 1900, it was in nearby Boxmoor JMI. He spent seven years at the school before leaving to take up work as a "Gardener", a job he still did when he volunteered. Of the thirty-two boys who went through school with Leonard, eight were to die in the Great War, more than a quarter, a common statistic in schools across the country.

On the outbreak of war Leonard volunteered almost immediately, when he attested at Hemel Hempstead and enlisted with the Royal Garrison Artillery (RGA), which was in the process of becoming a very important component of the British Army. The RGA significantly increased in size, especially the Heavy Batteries, which increased from thirty two Regular and Territorial Force batteries in 1914, to 117 by the end of the war. Leonard was sent for basic training to No.1 Depot, Newhaven in November 1914. He was then posted to the 37th Siege Battery RGA at Lydd in Kent, where he was given more specialist training in using the 6 inch (30cwt) Howitzer.

Siege Batteries like the 37th, increased from just three Regular batteries in 1914 to 401 by the time of Lenord's enlistment. They were equipped with heavy calibre weapons, such as 6 inch, 8 inch or 9.2 inch howitzers, and some had huge railway or road-mounted 12 inch howitzers. As British artillery tactics developed, the Siege Batteries were most often employed in destroying or neutralising the enemy artillery, as well as putting destructive fire down on strongpoints, dumps, store, roads and railways behind enemy lines.

Leonard went overseas on the 15th December 1915, departing from Devonport and sailing for Egypt, where he disembarked at Port Said on the 29th December. The 37th Siege Battery spent only four months in the middle-east, following the allied withdrawal from Gallipoli, and it subsequently transferred to France, landing at Marseille in April 1916. Leonard spent the next year around the Franco-Belgian border with his battery until December 1917, when the Royal Garrison Artillery was reorganised. The 37th Siege Battery transferred at that point, from the 79th Heavy Artillery Group, into the 59th Heavy Artillery Group of the II Corps.

A move to the Ypres Salient followed at the end of February 1918 and the Divisional War Diaries recorded two events which described briefly the experiences of the 37th Siege Battery. “22nd March 37th SB [Siege Battery] shelled again today. This battery has been shelled intermittently for the past three days.” This gives an indication that even well behind the front line the allied troops were not safe from enemy artillery. Then, eight days later, the following was recorded: “37th SB shelled with aeroplane observation inflicting casualties. Battery pulled out at night and went into their alternate positions.”  This diary entry gives an example of how the artillery from both sides made use of their nascent air forces, to observe the enemy and communicate positions, thus improving the accuracy of shelling.

It was during one of these attacks that Leonard was wounded and taken out of the line to 62nd Casualty Clearing Station (CCS) near Haringhe in Belgium. Sadly, he did not recover and died of his wounds on Monday, 1st April 1918. 62nd CCS was known as ‘Bandagehem’, which like ‘Dozinghem’ and ‘Mendinghem’, were the popular names given by the troops to groups of casualty clearing stations posted to this area. A good example of the kind of wry soldiers humour which prevailed during the horrors of the entire conflict.

He was commemorated on the War Memorial plaque in the church of St John the Evangelist, Boxmoor.

Leonard is Remembered with Honour in Haringhe (Bandaghem) Military Cemetery, West Vlaanderen, Belgium, where he is interred in Grave II. A. 20. The inscription on his headstone, requested by his father William, reads “ONE OF THE DEAREST, ONE OF THE BEST, GOD GRANT TO HIM ETERNAL REST”

He was 22 years old when he died.

Leonard was eligible for the 1914-15 Star, the British War Medal and the Allied Victory Medal.