The Lowestoft builder's son with a thirst for adventure had been seeking his fortune in one of the remotest corners of the British empire when war broke out.
By March, 1916, having endured bouts of dysentery and malaria, the veteran of two campaigns was a sergeant attached to the 5th Machine Gun Company, bound for the Western Front.
Of his final movements during the spring and early summer of 1916 little is known beyond the fact that by late July he and his unit were part of an Australian force poised to extend the British advance on the Somme with a night attack near the shell-ravaged ruins of Pozières.
Like so many other actions that summer, the assault did not go to plan. Even as the troops were moving up to their assembly positions they were detected by the Germans facing them.
With flares turning night into day, a lethal mix of high-explosive and poison gas rained on the hapless Australians shortly before midnight on July 28.
Soon machine-gun fire was added to the deadly hail flailing the exposed troops, sending them scurrying for cover amid the cratered wasteland straddling the Bapaume road.
No-man's-land at zero hour on July 29, resembled a living nightmare, carpeted with dead and injured and shrouded in chaos and confusion.
Those who escaped the holocaust crept back. Those too badly wounded to move were left lying in the open, exposed to an inferno of fire that showed little sign of ceasing. As the night wore on, their cries could be heard through the din in the trenches where Claude Castleton's machine-gun party had gathered to support the attack.
His original task rendered redundant, Claude Castelton decided to act of his own volition.
While others around him sought whatever shelter they could find, he was seen 'amidst shrapnel and heavy machine-gun fire, rifle fire and gas' to leap out of his trench and dash into the inferno.
What appeared an act tantamount to suicide was crowned with success. Moments later, he emerged out of the fire-swept smog with a wounded man draped over his shoulder. Having left him in the trench, he then disappeared a second time and repeated the process.
His survival appeared miraculous. Twice he had braved a storm of fire that had paralysed his comrades, and twice he had come through unscathed, having rescued injured men on both occasions.
No sooner had he brought the second man in than he was off again. He made it as far as another wounded soldier, had hoisted him on to his back and was struggling back when his luck ran out.
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