Knox was educated at
Bedford Modern School. He worked as an engineer at
Bristol Docks and was commissioned in the Nuneaton Volunteer Company of the 2nd
Volunteer Battalion, the Royal Warwickshire Regiment in 1899. The unit later became the 7th Battalion of the Royal Warwickshire Regiment in 1908. The
territorial battalion formed part of the
143rd Brigade,
48th (South Midland) Division. Knox commanded the battalion from 1915 on the
Western Front, notably at the
Battle of the Somme and the
Third Battle of Ypres. Knox was awarded the
Distinguished Service Order (DSO) on 1 January 1917. A
Bar to the award was gazetted after his death; the citation in the supplement to the
London Gazette of 24 September reads: Knox was also
mentioned in despatches on five occasions. ==Death and memorials==