John O'Brien (Australian Army officer)
Major General John William Alexander O'Brien, (13 June 1908 – 27 May 1980) was a senior officer in the Australian Army during the Second World War. He was awarded the Distinguished Service Order for his service as commander of the 2/5th Field Regiment during the Syria–Lebanon Campaign. As Deputy Master General of the Ordnance he was involved in the development of the short 25-pounder and the Owen Gun. After the war he was the Australian supply and defence production representative in Washington, D.C., from 1951 to 1954, and the mayor of Woollahra from 1971 to 1972 and 1975 to 1976. Early life John William Alexander O'Brien was born in Collingwood, Victoria, on 13 June 1908, the only child of Henry Charles O'Brien, a policeman, and his wife Jeanne Doris Kerr. His father had served in the Boer War as a private in the 2nd Battalion, Australian Commonwealth Horse, and had served in the Militia. O'Brien was educated at Ivanhoe State School and St Patrick's College, East Melbourne. In 1925, he entered Working Men's College, where he studied civil engineering. That year he was a full-time student but the following year he secured a position as a draughtsman at Dorman Long