Source: Michael Doyle Their Name Liveth For Evermore: The Great War Roll of Honour for Leicestershire and Rutland.
He was the son of William Stroyan, a police constable, born 1851 in Kircudbrightshire, Scotland and his wife Mary Stroyan, born 1863 in Kircudbrightshire. John, a schoolboy, was born in 1893 in Mainsriddle, Kircudbrightshire, his siblings were, Agnes, a schoolgirl, born 1890, Peter, a schoolboy, born 1895 and Charles, a schoolboy, born 1896, all his siblings were born in Kircudbrightshire, in March 1901 the family home was at Creebridge Village, Minnigaff, Kircudbrightshire. His parents latterly resided at Path Cottage, Blackcraig, Newton Stewart, Wigtownshire, Scotland. John embarked to join the British Expeditionary Force in France on the 1st June 1915. He was awarded the 1914-15 Star, British and Victory medals.
The War Diary records: 19 Mar-16 – SURREY FARM. Situation quiet. Draft of 62 other ranks arrived.
On Friday April 14th 1916 The Melton Mowbray Times & Vale of Belvoir Gazette published the following article under the heading. “MELTON AND THE WAR.” – ANOTHER MELTON SOLDIER KILLED. His numerous friends in Melton will be sorry to learn that Corpl. John Stroyan, of the Highland Light Infantry, has been killed in action. A native of Scotland, he came to Melton Mowbray about three years ago in the employ of Mr. Hayes, fishmonger, Burton-st. Deceased enlisted twelve months last February, and subsequently went out to the front. He was soon wounded, but on recovering he rejoined his regiment, and has now been killed by a shot in the head.

Source: Leicestershire War Memorials Project.
The following information was submitted by K. Morrison, June 2016:

Two of John Stroyan's brothers were also killed. The three are named on the Minnigaff Parish War Memorial in Kirkcudbrightshire.

Pte. Wm. STROYAN.
William Stroyan, Private (9902) 1st Battalion, Cameron Highlanders. Age 32.
William was a farm servant when he enlisted as Private (5255) in the Camerons in March 1900. He was posted to the 1st Battalion in March 1902. In total he spent 12 years in the army, including in the South African Wars, before he was discharged in March 1912. He re-enlisted in August 1914 and joined his battalion in France in September.
Born 1882 at Mainsriddle, Southwick, Kirkcudbrightshire. Son of Police Constable William Stroyan and his first wife Lillian McLelland (Kelly) Stoyan.
Missing in action on 11 November 1914 and named on the Ypres (Menin Gate) Memorial, Belgium.
Also listed on the Southwick War Memorial.

and two of his brothers

Sgt. CHAS. STROYAN.
Charles Ferguson Stroyan, Sergeant (200489) 1st Battalion, Cameron Highlanders. Age 22.
Charles enlisted in November 1914 and served in the 2/4th Battalion before being transferred to 1st Battalion. He was killed at Givenchy.
Born 1896 at Mainsriddle, Colvend, Kirkcudbrightshire. Son of Police Constable William Stroyan and his second wife Mary (Galloway) Stroyan of Path Cottage, Blackcraig, Minnigaff.
Missing in action on 18 April 1918 and named on the Loos Memorial, France.
L.Cpl. JOHN STROYAN.
John Stroyan, Lance Corporal (18257) 11th Battalion, Highland Light Infantry. Age 23.
John had been an apprentice fishmonger with Stewart's of Newton Stewart and working as a fishmonger in Burton Street, Melton Mowbray in Leicestershire when he enlisted in January 1915. He joined his battalion in France in June and was wounded at Loos.
Born 1893 at Mainsriddle, Colvend, Kirkcudbrightshire. Son of Police Constable William Stroyan and his second wife Mary (Galloway) Stroyan of Path Cottage, Blackcraig, Minnigaff.
Killed in action on 19 March 1916 and buried in Tancrez Farm Cemetery, Belgium.
Also named on the Melton Mowbray War Memorial and on the St. Mary's Church memorial there.

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