4th Division ( New Zealand ) The 4th Division was one of three home defence divisions of the New Zealand Military Forces formed during World War II . The unit was established on 1 November 1941 and was responsible for protecting the southern part of New Zealand ' s North Island from invasion . The division was greatly reduced in size during 1943 and was disbanded on 1 April 1944 without seeing combat . History . As part of the preparations for the possible outbreak of war in the Pacific , the defensive forces stationed in New Zealand were expanded in late 1941 . On 1 November three new brigade headquarters were raised ( taking the total in the New Zealand Military Forces , as the New Zealand Army was then known , to seven ) , and three divisional headquarters were established to coordinate the units located in the Northern , Central and Southern Military Districts . Upon formation , the division in the Central Military District comprised two brigade groups . The New Zealand Military Forces were further expanded following the outbreak of the Pacific War . The Territorial Force ( which comprised reservist personnel ) was fully mobilised on 10 January 1942 , and reinforced by 7000 men who had originally enlisted in the New Zealand Expeditionary Force for overseas service . The role of the Territorial Force was to counter any Japanese landings in New Zealand , and it was organised into both mobile and fortress units . The Home Guard would support the Territorial units in the event of an invasion . In 1942 the three divisions stationed in New Zealand were transformed into mobile formations and renamed , and the Central Division became the 4th Division ; the divisions in the Northern and Southern Military Districts were redesignated the 1st and 5th Divisions respectively . The 4th Division ' s inaugural commander was Major General Norman Weir . As of mid 1942 , the main elements of the division were the 2nd Infantry Brigade which was based near Palmerston North and the 7th Brigade Group located near Masterton . The division also comprised a number of supporting reconnaissance , artillery , engineer and supply units which reported directly to the divisional headquarters . All Army units stationed in New Zealand were held at a high level of readiness to respond to a Japanese landing throughout 1942 , though beach defences ceased to be manned from August . In addition , Masterton was struck by an earthquake on 24 June ; following this disaster the 1st Battalion , Ruahine Regiment ( which formed part of the 7th Brigade Group ) patrolled the town and had to recover its colours from a ruined church . Brigadier Geoffrey Peren assumed command of the 4th Division at some point in 1942 and held this position until 1943 . Peren had commanded the 2nd Infantry Brigade during 1941 and 1942 , and was both a long - serving territorial soldier and the professor of agriculture at Massey University . Weir subsequently served overseas as the commanding officer of New Zealand Troops in Egypt . The forces stationed in New Zealand were considerably reduced as the threat of invasion passed . During early 1943 each of the three home defence divisions were cut from 22 , 358 to 11 , 530 men . The non - divisional units suffered even greater reductions . The New Zealand Government ordered a general stand - down of the defensive forces in the country on 28 June , which led to further reductions in the strength of units and a lower state of readiness . By the end of the year almost all of the Territorial Force personnel had been demobilised ( though they retained their uniforms and equipment ) , and only 44 soldiers were posted to the three divisional and seven brigade headquarters . The war situation continued to improve and the 4th Division , along with the other two divisions and almost all the remaining Territorial Force units , was disbanded on 1 April 1944 .