Runners-up spot for last year's winner Townend
New Zealand's Tim Price retained the lead he held after cross-country to take the title at the Land Rover Burghley Horse Trials with Ringwood Sky Boy.
Fifth last year, the pair produced one of just eight clear show jumping rounds to complete on 27.3, ahead of last year's winners Great Britain's Oliver Townend with Ballaghmor Class on 31.9 and New Zealand's Andrew Nicholson and Swallow Springs on 32.1.
2018 has been a year to remember for Tim and his wife Jonelle as this win means the pair now holds the Burghley, Luhmuhlen and Badminton CCI4* titles between them after Jonelle won the two Spring events.
Both riders now head off to the World Equestrian Games in the USA as key members of the New Zealand team.
A delighted Price enthused: "What a super year.
"Sky Boy deserves a good day - so often we nail two out of the three phases, so to finally pull them all together in a major competition is fantastic.
"This win means everything and I'm super proud of my horse."
Tim also finished 10th with the 'young Pretender' Bango, who also show jumped clear.
Despite being unable to defend his title after lowering a show jump with Ballaghmor Class, Townend admitted that he was just as proud of the 11-year-old as he has been last year.
He commented: "It's all about consistency.
"He's still only 11 and I've been telling people for years how good he is.
"He's proved that again today. For me, he turned into a professional this week and dug deep whereas last year he won out of naivety."
Townend also filled 12th place with Cooley SRS.
Nicholson's clear round on the 10-year-old Swallow Springs elevated them up the leaderboard from fifth after cross country.
They were also the only pair in the field to complete on their dressage score - an amazing achievement in what is the horse's four-star debut.
Nicholson said: "I'm very, very pleased with him.
"He got distracted by the crowds in the show jumping at Blenheim last year where he had three down, and felt a bit babyish at Bramham in the summer, but he was pure class here.
"He had a look at the TV camera as we came down to the treble but came back to me when I asked him to focus."
British riders filled the next five places.
Sarah Bullimore was fourth with Reve Du Rouet after jumping clear.
Bullimore commented: "I'm over the moon. I knew if I kept him focussed, he'd take care of the jumping and he did."
Piggy French and Vanir Kamira dropped from third overnight to fifth after the mare lowered the gate:
French admitted: "To be honest I think we were lucky to just have one down.
"I'm a bit disappointed but top five at Burghley is still a great result."
Harry Meade and Away Cruising also dropped two places from fourth to sixth after they too rolled a pole.
Show jumping is the gelding's weakest phase and one which Harry has had to work hard to manage.
He explained: "If you told me at the beginning of the week we'd just have one down I'd have taken that.
"He has got much better though which I think is a combination of him growing up and me preparing him in a very specific way."
South Luffenham rider Richard Jones had a fantastic competition and posted his best result to date with Alfies Clover in seventh.
The pair rose from 33rd after dressage courtesy of two superb jumping phases:
Jones said: "This results means everything but it's all about progression and hopefully we can come back in the future and win it."