[2] Maynard undertook officer training at the Royal Military College, Sandhurst, and then joined the Devonshire Regiment in 1890.
[1] In February 1899, Maynard was promoted to captain and returned to England where he was posted to the Second Battalion, Devonshire Regiment.
[1] He remained in the country for the next three years, first serving on the front line and then as a staff officer specialising in press censorship from September 1901 until the end of the war in May 1902.
[1] Having recovered from his illness, Maynard was appointed to the staff of the British Salonika Army in August 1916, "for special liaison duties with the French".
[1] Having reverted back to the rank of lieutenant colonel, he was made a general staff officer 1st grade on 5 August 1916.
[1][18] After almost one year in command of the brigade, part of the 27th Division, on the Macedonian front with the British Salonika Army, he was once more taken ill and was invalided to England.
[1] After convalescing in England, Maynard was selected in May 1918 to command the Allied Land Forces at Murmansk as part of the North Russia intervention.
[1][11] Their main opposition was the 100,000 strong force under the command of Rüdiger von der Goltz, until the armistice of 11 November 1918.
[11] Maynard would go on to publish a book about his time in Russia, and summarised its unique scenario: "it was carried out by one of the most motley forces ever created for the purpose of military operations, and under climatic conditions never experienced previously by British troops".
[27] In the 1919 New Year Honours, he was appointed Companion of the Order of the Bath (CB) "for valuable services rendered in connection with Military Operations in North Russia".
[28] On 1 August 1919, he was promoted to Knight Commander of the Order of the Bath (KBE), also "for valuable services rendered in connection with Military operations in North Russia", and thereby granted the title sir.
[30] By 1920, he had been appointed Commander (3rd class) of the Order of the White Eagle with swords by the King of the Serbs, Croats, and Slovenes.