Allan Russell was amongst the first volunteers to enlist, as his military number, 296, testifies. Ond of two sons and three daughter born to James Dickson Allen and his wife, Margaret Ann, nee Johnson, he was born in Hawthorn, but was living at 24 Jolimont Terrace, East Melbourne and working as a driver when he signed up at Prahran on 20 August, 1914. He was assigned to the 5th Battalion, which was recruited from Victoria within a fortnight of the declaration of war, and which, along with the 6th, 7th and 8th Battalions, formed the 2nd Brigade. He was then 21 years and 5 months old.

After initial training, the 5th Battalion left Australia on board HMAT Orvieto A3 for Egypt and then took part in the Anzac landing at Gallipoli in the second wave. Ten days later, they were transferred from Anzac Cove to Cape  Helles to help in the attack on the village of Krithia. The attack was a disaster, leaving the 5th battalion depleted by one-third its strength. The remaining soldiers, including Allan Russell, returned to help defend the beachead at Anzac Cove, but were then called upon to fight in the battle of Lone Pine.

By then, Allan Russell had left the Gallipoli Peninsula. Struck down by gastroenteritis on July, he had been admitted to the 2nd Field Ambulance, then the 1st Casualty Station, before being evacuated to hospital in Lemnos via the fleetsweeper Clacton. From Lemnos, he was transferred to Mudros, Egypt, and admitted to the No. 1 Australian Stat. Hospital. From here, he embarked for England on board the Aquitania on 18 September,  landing on 26 September, where he was admitted to the Southern General Hospital at Portsmouth.

While the 5th Battalion was evacuated to Egypt in December, then on to France in March, 1916, Allan Russell remained in England. He was taken off strength from the 5th Battalion and taken on strength in London, where he seems to have served as a guard at the 4th London General Hospital. He was still there on 12 April, 1916, when he was charged with quitting his post without permission, forfeiting 3 days' pay and awarded 28 days' detention.

With the detention completed, he left England via Weymouth and joined the 1 Australian Division Base Depot at Etaples on 29 May, 1916. From here, he left for the Western Front on 16 June, joining the 5th battalion on 23 June, 1916.. He was a bugler, but no mention is made of this in his military record. Within five days he was dead, along with other from his battalion, at the Battle of Pozieres. He was killed in action on 25 July, 1916, and his body was never recovered. No Red Cross files exist about his death, although two 5th Battalion soldiers who died on the same date, Charles George Ruggles and Reuben John Rule, have their deaths recorded. 

By 1920, his mother, who had received a pension on her son's death, was dead. His sister, Isabelle Rachinger, wrote to the army authorities, requesting that they forward her brother's war medals to her. In reply, the authorities asked whether Allan Russell had any brothers as 'brothers have higher claims than sisters'. In the event, the medals were sent to Les. Russell, of Derrinallum,  Victoria, Allan's older br0ther.

Allan Russell's name appears on the Australian Memoral at Villers-Brettoneux. In Australia, he is listed on the Roll of Honour Cards 145 and on Panel 45 in the Commemmorative Area of the Australian War Memorial.