George Henry Heaney used a false name when he enlisted on 8 July, 1915. His true surname was Hart, and he had a father and stepmother living in Sexton St., Highgate Hill, Brisbane, Queensland. Heaney was a cook by trade and 36 and 10 months old, and had already had six years service with the A.R.G.A. Initially, he was placed with the 39th Battalion, 8th Reinforcements, but quickly moved to the 31st Battalion. 

The 31st Battalion was made up of two companies raised in Victoria and two at Enoggera, Queensland, put together to form the new battalion prior to embarkation for Egypt and intended to swell the number of troops following the defeat at Gallipoli. George Heaney embarked from Brisbane on 9 November 1915, on board HMT Wandilla, disembarking at Suez on 7 December, 1915. Over the next months, the 31st Battalion took part in the defence of the Suez Canal against the Turkish forces. On 16 June, 1916, the Battalion left from Alexandria for France, disembarking from HMAT Hororata at Marseilles on 23 June.

From here, they left for the Western Front. Their first engagement was the battle of Fromelles and it was here, on the first day, that George Heaney was fatally wounded.

Lieutenant Still, 31st Battalion, wrote of Heaney's fate on 19/7/1916:

I saw him badly wounded beyond the German trenches. We had to retire. Heaney likely taken prisoner or killed.

The 31st Battalion suffered 500 casualties at Fromelles in the Somme Offensive. The Germans were anticipating the attack, which began at 6pm with three hours of light left, and quickly manned their machine guns, with disastrous results for the British forces. The 31st Battalion was 'so badly mauled that it undertook no more offensive action for the rest of the year'. In all the British Expeditionary Force suffered 7,080 casualties; there were 5,583 Australian dead. Heaney was reported missing on 19/7/1916. He was taken up by the German troops, with gunshot wounds to both legs, his left hip and below his left scapula and died on 25 July, 1916. He was buried at Haubourdin, Departement du Nord, which the German Army held from October 1914 to October 1918. Post war, the remains of all British soldiers, buried in Haubourdin were removed to the Cabaret Rouge British Cemetery at Souchez ,France. Heaney/ Hart lies in Plot 16, Row 'C', Grave 10.

His medals were given to his father.