John Fitzgerald was unusually tall for his generation, just over 6' 1". He was the son of John Fitzgerald and Elizabeth Travers Fitzgerald, born in Lilydale, Victoria. He was 29 years old when he enlisted, marrying his sweetheart, Eileen Mary Bascombe, the eldest daughter of Herbert Bascombe of 50 Gipps St., East Melbourne, before he left for the war. The ceremony was at St. Patrick's Cathedral, East Melbourne on 20 July, 1915, a week after he enlisted and Eileen continued to live with her father while John Fitzgerald was away.

John Fitzgerald was called up on 22 July, 1915, just two days after his marriage, training in Melbourne for the rest of the year, first with A Company, 12th Depot Battalion and then with the 9th Reinforcements, 21st Battalion. On 8 February, the 21st Battalion 1-12 recruits left Melbourne for Suez, on board HMAT Warilda. A69, bound for Suez. From here, they were sent on to France on HMT Oriana, leaving Alexandria on 21 March, 1916 and disembarking at Marseilles on 27 March. On 10 June, they joined the rest of the 21st Battalion in France.

The 21st Battalion had taken part in the Gallipoli Campaign, but then moved to the Western Front from Suez in March, 1916. They were the first of the Australian battalions to be commence active operations on the Western Front. The new recruits joined the battalion  on 10 June. In July, 1916, they were at Pozieres, though mainly involved in dealing with equipment. In August, they were part of the action at Moquet Farm and suffered their most significant losses of the war. John Fitzgerald was probably at Moquet Farm, but on 27 August, he was taken ill and sent ot the 4th Casualty Clearing Station, before being admitted to the 10th General Hospital at Camiers. From here, he was moved out ot England, leaving France on board the Stat Antwerpen from Calais on 2 October, 1916. Here he was discharged to furlough and then sent to convalescence at Perham Downs.

In February, he returned to his battalion, moving to Folkestone on 1st February, then catching the SS Victoria back to France, rejoining the 21st Battalion on 8 February. It was a very bitter winter, though, and in March, he was again in hospital, this time with influenza. He was not discharged to duty until 7 April, 1917, rejoining the battalion on 14 February.

In May, the 2nd Australian Division, consisting of the 5th and 6th Brigades, joined the British 62nd division in separate attacks on the fortified village of Bullecourt. On 3 May, at 3.45 am, they began the attack, meeting with  fierce German resistance. The Australian troops penetrated the German lines, but suffered a ferocious counter-attack. The battle continued until the Germans withdrew on 15 May.

The casualties were high from the 2nd Battle of Bullecourt: 7,482 from the Australian divisions. John Fitzgerald died on 5 May. Although he is listed on the Red Cross files, there were no witnesses to his death and his body was never recovered. He is listed on a the Villers-Bretonneux Memorial, Villers Bretonneux, France, on the Australian War Memorial Roll of Honour Cards and on Panel 93  in the Commemorative Area of the Shrine of Remembrance.