There is nothing in Bert Harris's military record that places him anywhere near East Melbourne at the time of the Great War. He grew up in New Zealand and enlisted at Casula, NSW. He gave as his next of kin his brother, Albert, living at Aratapu, and enlisted on 23/11/1915 following on from the defeat at Gallipoli. At this time, he was 28 years old, and described himself as 5' 10", tall for those times, with a dark complexion, black hair and brown eyes. He seems to have been placed initially with the Anzac Provost Corps. On 24 February, 1916, he was placed with the 2nd Light Horse Training Regiment and then the 4th Light Horse. By 19 March, he was in Egypt, with the 12 Light Horse Training Regiment, taken on strength at Moascar.

On 10 August, he had an accident, a fall from his horse, resulting in a dangerous skull injury and concussion. For a time, he was not expected to live. A cable was sent to Defence, Melbourne: '... dangerously ill, fall from a horse'. However, another cable was sent from Cairo on 17 September, 1916, with the message 'Removed from danger list, progressing favourably.'  Bert Harris had been discharged by then from the 24th Stationary Hospital and rejoined the Light Horse. He must have recovered well, because on 27 September, he was arrested  for being AWOL from 27 - 30 September, when he was arrested by Military Police in Cairo. For this offence, he was given 7 days Field Punishment No 2 and the forfeiture of 21 days pay. Field punishment involved heavy manual labour.

)n 5 October, 1916, he left Cairo and was taken on strength on 5 October at Moascar, where on 12 October, he committed another offence. He was duly charged with 'Conduct to the prejudice of good order and military discipline when in charge of a government horse. He improperly rode the the same at a racing pace, causing death of same horse to the value of 30 pounds.' For this, he was forfeited 40 days pay. 

Again on 1 February, 1917, he was caught '... out of bounds, being in the Sergeants' Mess'. he was given 7 Days Field Punishment No. 2. ' He returned to  duty, but on 10  April 1917 and again on 14 April at Sheik Zouwaid he was charged with drunkenness on active service. And on 24 July, he was charged with creating a disturbance, using obscene language and giving a false name and regiment to the Military Police who arrested him.

On 9 April, 1918, he sent to hospital with synovitis of the leg; it was perhaps the same leg that turned septic on 1 May the same year. He must have been quite ill, because on 13 May, he was taken on strength from a rest camp in Port Said. However, on 2 November, he left camp without permission, staying away 24 hours. 

On 11 November, 1918, the war came to an end. It must have been a great relief for the troops, but again, Bert Harris kept getting into trouble. He was in hospital on 2 February, 1919, with piles, but on 3 February,1919, had an accident, which left him with a fracture to his right clavicle and right patella. At the hearing, he said that his horse had slipped on a greasy road on their way back from the waterhole and, because there were no witnesses,  his version of the event had to be accepted. Bert Harris was still in Cairo, and as preparations increased to send the troops home, on 22 March, 1919  he was charged that at Cairo on 17 March, he had shown 'conduct to the prejudice of good order and military discipline in that he he, at about 19.20, when ordered to report to the Kit Stores, failed to do so and attempted to cause a disturbance and entice soldiers to follow him with intent to cause trouble'. 

He finally embarked for home on RMS Mongolia, leaving on on 8 July and landing in Sydney. His record subsequent to his first accident may have produced the erratic behavious he exhibited, but no medical records are attached to his army record.