He saw WW2 service with 15th Australian Infantry Battalion in the SW Pacific Theatre where he was wounded. While recovering he served for a time as ADC to Lieutenant General Sir Frank Berryman.

In the mid-1950s he served during the Malayan Emergency as Brigade Major of 28th British Commonwealth Independent Infantry Brigade during which time he was Mentioned in Despatches.

Following a series of appointments in the ranks of Major and Lieutenant Colonel he was promoted temporarily to Colonel and appointed as the Australian Services Attache in Saigon. He held this appointment from 16th December 1962 until 25th January 1965.

In early 1965 he reverted to his substantive rank of Lieutenant Colonel and was appointed Commanding Officer effective upon the formation of the Battalion on 1st March 1965. From the outset, the Battalion had been made well aware of impending operational service in South Vietnam, possibly within twelve months. Administrative Command was vested in the Battalion Second in Command until the new CO arrived in early April. The 2IC, Major J A Warr, was slated to become CO from 1st September. Allowing his nominated successor a free hand to get on with all aspects of detailed preparations for war, he set about imbuing the newest addition to the Royal Australian Regiment with an indelible sense of identity and esprit de corps which it has maintained ever since. The collegial approach of these two men and their readily agreed division of what were, in many ways, shared responsibilities was understood and respected by all. Any notion of divided loyalties never arose.

After just six months he relinquished command to his successor, the now Lieutenant Colonel John Warr, and left on promotion to Colonel to raise the new 3rd Training Battalion at Singleton. In a short but energetic tenure of command his emphasis on welding the newly raised 5RAR into a cohesive and proud assemblage of Regular soldiery was both a gift and a legacy. As the Battalion’s National Servicemen began arriving in September this spirit was eagerly adopted by the newcomers and the integration of its two components proved seamless. The most enduring of his many morale building initiatives was his conception and promotion of the sobriquet The Tiger Battalion which was enthusiastically adopted by all ranks. He liked to do things with a flourish, either verbally or by example, and was a great choice for the inaugural CO of an Infantry battalion. In 1972 he was made an Officer of the Most Excellent Order of the British Empire.

Colonel Peter Oxley died prematurely on 5th October 1981, aged 58 years and nine months. He is buried in Gungahlin Cemetery, Canberra.