Leading from the start of the competition, driving icon Exell finished the Cones phase just one second over time, adding 0.53 points to his final score of 154.14 for his dark bay four-in-hand-team, led by his stellar black gelding Zindgraaf.
"This win was a huge relief because we have a big group of people that have been with me for 25 years. I am super lucky to have such extremely good horses. They absorbed the crowd's enthusiasm and I was able to support them."
On home ground, Team USA represented by Chester Weber, Misdee Wrigley-Miller and James Fairclough delivered a start-to-finish-victory, ending on 353.39 points in front of the Netherlands (356.79) and Belgium.
"It's unbelievable. It takes a village to make this whole thing work - I said all week that I was going to keep my head down and concentrate on my own game and hopefully on Sunday I'll pick my head up with a medal or two around it," said Chester Weber.
World's No. 2 driver and four-time WEG-competitor Weber was the strongest driver in all three phases for the U.S. The 43 year-old multiple National Champion, defended his Individual Silver from WEG 2014 with ease, adding only 2.77 points for time in the Cones phase to his result after Dressage and Marathon.
"It is humbling. When I started as a 13-year old. James Fairclough was my teacher and now we were winning in one team."
Historic driving powerhouse The Netherlands lost their world title and kept Silver for Koos de Ronde and Ijsbrand and Bram Chardon. Both Chardons had mistakes in the Marathon and fought hard in the cones course.
WEG-novice Bram Chardon (25) was the only driver in a field of 19 competitors to stay clear within the time, winning the cones phase.
"I did not sleep at all, thinking all night about what I had to do today. I wanted to prove myself and I knew I had what it takes."