James Mackenzie was born in the district of Lochs Ross & Cromarty in 1891.Son of John Mackenzie of ‘Woodlands’, Lairg and Henrietta Munro. They were married in 1875 in Tongue. The Duke of Sutherland employed him, alongside his father as a gamekeeper before James emigrated to New Zealand with his brothers Donald and Joseph. In 1911 Census James is with his widowed mother and brother Sinclair is listed as head of household. James's occupation is listed as Postman.

He enlisted into the New Zealand Armed Forces and served in France with the New Zealand Machine Gun Corps. The Machine Gun Corps had been formed in France in January 1916 and was in action during the Battle of the Somme in September, when the New Zealand Division took part in the attack on Flers-Courcellette.

In June 1917, the New Zealand Division was in the Ypres sector of the front line preparing to attack the Messines Ridge, south of the town of Ypres close to the French and Belgian borders. ‘Operation Northern’ was the plan to seize the ground South of the Ypres Salient in preparation for the Third Battle of Ypres, to be launched in July.

On the 7 of June 1917, at 3:10 am the British Royal Engineers exploded nineteen mines, containing almost one million pounds of high explosives under the German trenches on the Messines Ridge. The New Zealand Division then advanced under a heavy smoke screen and creeping barrage, quickly overcoming the dazed and terrified enemy survivors. The explosion was so loud it was heard in London, twenty one mines had been planted one of the remaining two exploded in 1955 when it was hit by lighting, the other lies unexploded under the fields at Messines today.

The ridge was taken by 9:am with light casualties, the advance was then continued in the afternoon and that was when the casualties began to occur. The troops were soon very overcrowded on top of the ridge and came under heavy artillery fire, some of it from the British guns behind them. The line was then consolidated with further attacks being made on the ruined village of Wytschaete and the southern shoulder of the ridge.

Within three days the Messines Ridge and the German trenches on the Oosttarvne Line had been taken for a total casualty loss of 25,000 men, German losses totaled 23,000 men including 10,000 who were missing.

Private James Mackenzie was severely wounded as his unit attacked the Southern end of Messines Ridge. He was taken to the 2 Australian Casualty Clearing Station where he died from his wounds three weeks later; he was 26 years of age.

James was one of five sons and one daughter from the same family to serve in the First World War. Joseph, Sinclair and Isabella were all killed during the war, Donald who was severely wounded and John both survived the war returning home to their family in Lairg.