Edgar Leslie Cecil Willis Walker Maygar was born on his parents' property near Kilmore, Victoria on 27 May 1868. The seventh son of Edwin Willis and Helen (nee Grimshaw) Maygar, he was educated at Alexandra and Kilmore public schools. Later, in partnership with his father and brothers, he bought Strathearn Station, near Longwood, Euroa. A highly proficient horseman, he enlisted as a volunteer in the Victorian Mounted Rifles in March 1891.
With the outbreak of war in South Africa in 1899, Magyar was keen to enlist but was initially rejected for service due to dental problems before being accepted in the 5th Contingent of the Victorian Mounted Rifles. For his actions during fighting near Geelhoutboom on 23 November 1901, he was awarded the Victoria Cross.
On his return to Australia Maygar resumed his pre-war occupation on the land near Euroa. He also continued as a lieutenant in the militia with the 8th Light Horse Regiment and later as a captain with the 16th. On 2 November 1912, for his long military service he was awarded the Colonial Auxiliary Forces Long Service Medal. With the outbreak of the First World War on 4 August 1914, Maygar immediately offered his services and within three weeks was appointed a captain commanding B Squadron of the 4th Light Horse Regiment (LHR). On 19 October, he embarked with his unit for Egypt, arriving in Alexandria on 11 December. In January 1915, Maygar was promoted to major.
Following training, the regiment moved to Gallipoli as an unmounted unit, landing there on 24 May. For the next few months, 4LHR were deployed at Ryrie's, Lone Pine, Courtney's Post and Leane's Trenches. On 17 October, Maygar was promoted to temporary lieutenant colonel and given command of 8LHR. The regiment was evacuated from the Peninsula on 20 December.
The move to Egypt saw the regiment reunited with their horses before moving east for operations in Sinai and Palestine, as part of Major General Harry Chauvel's Anzac Mounted Division. In August 1916, 8LHR was involved in heavy action pushing the advance following the battle for Romani, and later contributed to operations at Sagia and Hod el Bada.
In December, the Anzac Mounted Division was ordered to capture the enemy held village of Magdhaba. The assault on 23 December, with 8LHR attacking from a ridge north of the village, almost met with failure when strong resistance delayed the capture of vital water supplies. Just as Chauvel proposed a withdrawal, 1 Light Horse Brigade broke through, signalling a change of fortune, and within hours the objective was taken. During the assault 8LHR lost five officers and ten other ranks either killed or wounded.
In January 1917, 8LHR, though playing a reserve role in the assault on Rafa, provided outposts against a large column of enemy reinforcements. In March and April the regiment fought in the failed attacks on Gaza. During heavy fighting in the second attempt, on 19 April, 8LHR found itself exposed in a gap created when two flanking brigades were forced to diverge. By 4pm it was obvious the attack had failed and the decision was made to withdraw, by which time the regiment had suffered 73 casualties. Official historian H S Gullet said of Maygar's conduct during the fighting that: 'It was a day when true leaders recognised that their men needed inspiration, and Maygar gave it in the finest manner.'
For his leadership during the attacks at Maghdaba and Rafa, Maygar was awarded the Distinguished Service Order on 3 June. Four days later, in recognition of his long and distinguished military career, he was awarded the Colonial Auxiliary Forces Officer's Decoration.
On the afternoon of 31 October, at Beersheba, Maygar was severely wounded during a German aerial attack. Despite surgery to remove his shattered arm he died from blood loss the following day. Maygar is buried in grave number Q 82 of the Beersheba War Cemetery.