His class graduated early after the First World War broke out, and he served on the Western Front with the field artillery.

Berryman joined the Second Australian Imperial Force (AIF) on 4 April 1940 with the rank of full colonel, and became General Staff Officer Grade 1 (GSO1) of the 6th Division.

Berryman hoped to become Chief of the General Staff but was passed over as he was seen as a "Blamey man" by Prime Minister Ben Chifley.

[6] Of the 33 members in his class, nine died in the First World War, and six later became generals: Leslie Beavis, Berryman, William Bridgeford, John Chapman, Edward Milford and Alan Vasey.

Berryman rose to fifth in order of merit before his class graduated early, in June 1915, because of the outbreak of the First World War.

When asked if they would prefer the technical services, twelve cadets, including Berryman, Beavis, Clowes, Vasey, and Wackett stepped forward.

This policy was aimed at giving them a broad range of experience, which would benefit the Army, while not allowing them to outnumber the available post-war positions.

In particular he did a very fine piece of work on 14th September in moving his Battery forward behind Clapham Junction in the dusk under very heavy shelling over a very difficult road.

[20] His citation, signed by Major General Charles Rosenthal, read: This officer has commanded the 14th Battery from 8th May 1918 to the present date [September 1918].

The work and appearance of his Battery both when in and out of the line, has been excellent, and his sound judgement and technical ability have been of the greatest assistance to his Brigade.

[21]Berryman was later nominated for a bar to his Distinguished Service Order for the September 1918 fighting, but this was subsequently downgraded to a second Mention in Despatches.

"[32] After graduation he was posted to the High Commission of Australia, London, from 1929 to 1932,[33] where he served under the Military Liaison Officer, Major General Julius Bruche.

"[35] Berryman joined the Second AIF on 4 April 1940 with the rank of full colonel, receiving the AIF serial number of VX20308,[11] and became General Staff Officer Grade 1 (GSO1) of Major General Iven Mackay's 6th Division, in succession to Sydney Rowell who stepped up to become chief of staff of I Corps.

This meant that while Berryman viewed some Militia officers, like Brigadier Stanley Savige of the 17th Infantry Brigade, with disdain, he maintained good relations with others.

Yet even those who disliked Berryman personally for his lack of patience and tact and referred to him as "Berry the Bastard" respected his abilities as a staff officer.

Though at times he proved secretive and hard to deal with, during the battle his forceful personality provided a good foil to the sometimes indecisive Mackay.

[43] In January 1941, Berryman became Commander, Royal Artillery, in Arthur "Tubby" Allen's 7th Division, and was promoted to brigadier.

[48] In the final stage of the battle, Berryman, without authority, ordered Lieutenant Colonel Denzil MacArthur-Onslow of the 2/6th Cavalry Regiment to pursue the retreating French forces, but was overruled by Savige and Allen.

Berryman arrived in Jakarta by air with the advanced party of the I Corps headquarters staff on 26 January 1942 to plan its defence.

[54] When New Guinea Force split into a rear headquarters under Blamey and an advanced headquarters under Lieutenant General Edmund Herring, so the latter could go forward to direct the Battle of Buna-Gona, Blamey brought Berryman up from Advanced LHQ in Brisbane to simultaneously act as chief of staff of New Guinea Force from 11 December 1942.

His achievements in keeping the peace were of no mean order in light of America's preponderant contribution to the overall forces under MacArthur's command.

[64] When Berryman discovered that the United States Seventh Fleet did not intend to reinforce the 9th Division he immediately went to Blamey, who took the matter up with MacArthur.

In the event it was Berryman who brokered a compromise deal with Vice Admiral Arthur S. Carpender to reinforce Finschhafen with a battalion in APDs.

[65] On 7 November 1943, Berryman became acting commander of II Corps, a post which became permanent on 20 January 1944, superseding Vasey, whose 7th Division was diplomatically placed directly under Lieutenant General Sir Leslie Morshead's New Guinea Force.

Whenever the Japanese Army attempted to make a stand, Berryman attacked with 25-pounder artillery barrages and Matilda tanks.

In preparation for the Philippines Campaign, General MacArthur moved the advanced element of GHQ to Hollandia in Dutch West Papua, where it opened in late August 1944.

[24] As well as liaising with GHQ, Forward Echelon LHQ became responsible for planning operations involving Australian troops.

It worked on plans for operations on Luzon and Mindanao before it was finally decided that Borneo would be the Australian Army's next objective.

In all of this Berrymen kept in close contact with Blamey, and the two were Australian Army representatives at the Japanese surrender in Tokyo Bay in September 1945.

[38][73][74][75] Berryman became known for his involvement in charitable organisations such as the War Widows Association, and as head of the Remembrance Drive Project.