 During the Gallipoli Campaign four light horse brigades had been dismounted and fought alongside the infantry divisions . However , in March 1916 the ANZAC Mounted Division was formed in Egypt ( so named because it contained one mounted brigade from New Zealand – the New Zealand Mounted Rifles Brigade ) . Likewise , the Australian Mounted Division — formed in February 1917 — was originally named the Imperial Mounted Division because it contained the British 5th and 6th Mounted Brigades . Each division consisted of three mounted light horse brigades . A light horse brigade consisted of three regiments . Each regiment included three squadrons of four troops and a machine @-@ gun section . The initial strength of a regiment was around 500 men , although its establishment changed throughout the war . In 1916 , the machine @-@ gun sections of each regiment were concentrated as squadrons at brigade @-@ level . Like the infantry , the light horse regiments were raised on a territorial basis by state and were identified numerically ( 1st to 15th ) . 
