|Place of birth||Jamestown South Australia|
|Address||Kintore Street, Mile End, South Australia|
|Age at embarkation||21|
|Next of kin||Mother, Mrs J J 0'Neil, Kintore Street, Mile End, South Australia|
|Date of enlistment from Nominal Roll|
|Rank on enlistment||Private|
|Unit name||12th Battalion, E Company|
|AWM Embarkation Roll number||23/29/1|
|Embarkation details||Unit embarked from Hobart, Tasmania, on board Transport A2 Geelong on
|Rank from Nominal Roll||Corporal|
|Unit from Nominal Roll||12th Battalion|
|Recommendations (Medals and Awards)||
'For gallantry and devotion to duty at Meteren on 23 April 1918.'
|Fate||Returned to Australia
'For gallantry and devotion to duty at METEREN on 23rd April, 1918. Corporal O'NEIL led a section of bombers in an attack on the enemy's position. He personally bombed a machine gun which was causing causlaties, killing several of the crew and capturing the gun. He then led his men with great skill in a bombing attack down the trench and cleared same. Although wounded at the beginning of the attack he carried on and only led when ordered by his platoon commander. He set a fine example of courage and devotion to duty to his men. Wounded in back, not severe.'
Source: 'Commonwealth Gazette' No. 1