He was posthumously awarded the Victoria Cross for his efforts to save his regiment's colours after the Battle of Isandlwana, the first major engagement of the Zulu War.

[6] In England attending the Staff College at Camberley when the First World War broke out, Melvill returned to his former unit, the South Lancashire Regiment.

He then served as brigade major for the Tay Defences from May to September 1915 before transferring to the New Zealand Expeditionary Force (NZEF), which at the time was engaged in the Gallipoli campaign.

[11] During the German spring offensive of 1918, Operation Michael, Melvill's brigade played key roles in holding and stabilising the lines in the New Zealand sector.

Well regarded for his capable leadership, he also led the New Zealand Division from late-June to mid-July 1918 while its nominal commander, Major General Andrew Russell was on sick leave.

In the Hundred Days Offensive, his leadership of 1st Infantry Brigade saw it breach the Hindenburg Line and capture the town of Crevecoeur during the Battle of the Canal du Nord on 28 September.

Survived by his wife, Rita Burnett, whom he had married in 1911, he was buried with full military honours[1] in the servicemen's section of Wellington's Karori Cemetery.