James Beechey, who was 40, was a serving Major in the British Army and a multiple Ironman triathlon/marathon/ultra marathon finisher.
He tragically died “far too young” after a short but determined battle against bowel cancer, said an army spokesman.
James leaves behind a wife, Samantha, daughter Olivia aged three and one-year-old son George.
The funeral was held last Thursday at Crownhill Crematorium and hundreds attended to say goodbye. The procession was lined by fellow army officers, led by a piper and soldiers of the Scottish Gunners and rounded off with a seven-gun salute.
James graduated from Sandhurst Military Academy. Commissioning into the Royal Artillery, he served as a Troop Commander (on operations), Fire Support Team Commander, Battery Commander and a senior instructor.
He served two tours in Afghanistan and also passed selection for P-Company, earning his airborne wings and the coveted maroon beret.
Fellow Officer Luke Malpass said: “James trained and led us with his own unique style, a style that had always and would always set him apart - he was aggressive, professional, knowledgeable, fiercely determined, fit and quietly paternal, and we took to that style
straight away. You simply didn’t want to let him down.
“On his second tour of Afghanistan he led an infantry company in the attack, something that hadn’t been done for some time, and we had a terrible day on account of a horrendous injury to a soldier in an IED blast.
"James got us off the ground and back to safety under fire and coordinated a timely medevac that saved that soldier’s life - a soldier who earlier this week stated that James was quite simply among the finest officers and men he’d ever known.”
James, who swam for City of Milton Keynes Swimming Club throughout his teenage years. competed in many sports and excelled at Ironman distance triathlon. He completed six of these races, with a personal best of 9 hours and 34 minutes.
He also was a keen runner, often representing MK’s Redway Runners.
A loving and dedicated husband, he was cared for in his final weeks by Willen Hospice, and donations to this charity are welcome.