A professional soldier, Vasey graduated from Royal Military College, Duntroon in 1915 and served on the Western Front with the Australian Imperial Force, for which he was awarded the Distinguished Service Order and twice Mentioned in Despatches.

For nearly twenty years, Vasey remained in the rank of major, serving on staff posts in Australia and with the Indian Army.

Shortly after the outbreak of Second World War in September 1939, Lieutenant General Sir Thomas Blamey appointed Vasey to the staff of the 6th Division.

While flying to assume this new command, the RAAF Lockheed Hudson aircraft he was travelling in crashed into the sea, killing all on board.

[2] He was educated at Camberwell Grammar School and Wesley College, Melbourne, where his schoolmates included Robert Menzies and Edward James Milford.

Six later became generals: Leslie Beavis, Frank Horton Berryman, William Bridgeford, John Chapman, Edward James Milford and Vasey himself.

The 2nd Division moved to France in March 1916, where Vasey was promoted to captain in August, and given command of the 13th Field Battery in November.

In February 1917 Vasey was posted to Brigadier General James Cannan's 11th Infantry Brigade as a trainee staff captain.

[8] His recommendation read: During the periods October 4th and 12th 1917, as brigade major this officer worked continuously day and night with untiring effort and devotion to duty.

In July and August 1917 near Warneton this officer showed conspicuous gallantry in action in supervising the work of the battalions in the forward line without any fear for his personal safety in a way that was most eminently satisfactory and deserving of the highest praise.

[24] Gavin Long noted that Vasey was "highly strung, thrustful, hard working... concealed a deeply emotional even sentimental nature behind a mask of laconic and blunt speech.

[27] In March 1941, Vasey was promoted to temporary brigadier and took command of the 6th Division's 19th Infantry Brigade following the departure of Horace Robertson to Australia on medical grounds.

[32] Although it was a bitter defeat, Vasey's performance was considered outstanding; he was appointed a Commander of the Order of the British Empire (CBE),[33] awarded a Bar to his DSO,[34] and later the Greek War Cross.

Vasey returned to Australia in December 1941 to become Chief of Staff of Home Forces, with the rank of major general, which became substantive on 1 September 1942.

[38] With the establishment of Advanced Land Headquarters (Landops) at St Lucia, Queensland, Vasey became the principal operational staff officer there.

[40] Later that month, General Douglas MacArthur and Prime Minister John Curtin ordered Blamey to take personal command of New Guinea Force.

After a falling out, Blamey relieved first Rowell, replacing him with Herring,[41] and then Major General Arthur "Tubby" Allen of the 7th Division.

[44] The division was forced to fight a bloody battle around Buna, and, together with American troops under Lieutenant General Robert L. Eichelberger, ultimately defeated the Japanese and captured Gona.

[48] Probably inspired by his experience on Crete, Vasey proposed using paratroops, and pressed his superiors for an entire regiment instead of the battalion he was originally allotted.

They were soon reinforced by Australian and Papuan troops that had advanced overland from Wau, and then by the 7th Division's 25th Infantry Brigade, which flew in by air.

Vasey was drinking heavily,[60] and was hospitalised in New Guinea in February 1944 with a skin condition,[61] and again in Australia in March 1944 with a respiratory tract infection.

In October 1944, Blamey set up a Post-War Army Planning Committee headed by Vasey to report on the future of the Royal Military College and the training and education of Staff Corps officers.

Due to a cyclone that was ravaging the Queensland coast at the time, the aircraft crashed into the sea about 400 metres (440 yd) out from Machans Beach, just north of the mouth of the Barron River, 2 kilometres (1.2 mi) short of the Cairns Airport.

[71] Vasey's body was recovered from the crash site and was buried with full military honours in Cairns cemetery along with those of Downes and Lieutenant Colonel G. A. Bertram.

For pall bearers, Vasey had Major Generals Edward Milford and George Wootten and Brigadiers Frederick Chilton, Ivan Dougherty, Kenneth Eather, John O'Brien, Henry Wells and David Whitehead.

[76] Historian David Horner wrote: "Not only was his command marked by tactical flair, innovation and imagination, but he also displayed remarkable qualities of leadership in adverse situations.

"[77] Today, Vasey's papers are in the National Library of Australia,[78] and his decorations are held by the Australian War Memorial,[79] as is his portrait.