Joe Salisbury and Harriet Dart clinched Battle of the Brits victory for their team after beating Jamie Murray and Heather Watson in a winner-takes-all decider on a thrilling final day.
Salisbury and Dart won 6-4 6-2 to seal a 63-56 win for the British Bulldogs.
Union Jacks pair Andy Murray and Naomi Broady set up the deciding rubber by winning the penultimate match of the week-long tournament in Roehampton.
But Salisbury and Dart dominated the decider as the Bulldogs celebrated.
With the sides tied at 45-45 going into Sunday, the Bulldogs won six of the 10 matches on the final day in an innovative format where matches were worth different points.
"It has been an amazing week, everything I thought it could be," said tournament organiser Jamie Murray.
The 34-year-old Scot set up the week-long event to provide competitive action for British players while the professional tours remain suspended because of the coronavirus pandemic.
The country's leading men and women have played together in singles, doubles and mixed doubles matches in the unique team event.
"Events like this are perfect not just for the tour players but the younger players to get ready and get back out there," said British men's number one Dan Evans.
"Without these events none of us would be in such a good position and hopefully there should be some British success when we get back."
How are the Brits shaping up for the professional restart?
With the ATP and WTA Tours suspended since March and resuming this month, the Battle of the Brits allowed the players to build up fitness and sharpness in a competitive environment.
Former world number one Andy Murray only played in the doubles as he continued to build up his fitness after struggling with pelvic and shin injuries this year.
The 33-year-old Scot is planning to play the Cincinnati Masters and the US Open, which are being held in a two-tournament safety bubble in New York when the ATP Tour on 22 August.
"My game is in a decent place but it is tough to comment about the body until I'm out there playing competitive singles matches, that's where it will really get tested," Murray said.
"I feel I've played pretty well in the matches and the basics of the game, serving and returning, have been good."
Britain's leading women's players, Konta and Watson, are also planning to return to the professional tour in the States at the WTA tournament in Lexington next week.
Konta, ranked 14th in the world, had not played since the tour was suspended in March and, after losing her opening match to Jodie Burrage, improved as the week wore on at the National Tennis Centre.
But the 29-year-old, who has been managing a knee tendon problem this year, did not play at all on Sunday.
Watson, ranked 50th in the world, maintained her 100% winning record in the singles by beating Beth Grey for a fifth victory.
Evans says his game is in a "good spot" before the restart of the tour, while British men's number two Edmund says he is raring to return to professional action after winning his fourth singles matches in a row.
Union Jacks: 56-63 British Bulldogs (first to 60)
(Matches show Union Jacks players first)
Anton Matusevich 6-3 6-2 Alastair Gray (2pts)
Naomi Broady 3-6 3-6 Emma Raducanu (2pts)
Jan Choinski 2-6 1-6 Kyle Edmund (3pts)
Jodie Burrage 4-6 6-7 (5-7) Harriet Dart (3pts)
Andy Murray/Naomi Broady 6-3 7-6 (7-5) Kyle Edmund/Emma Raducanu (4pts)
Jamie Murray/Heather Watson 4-6 2-6 Joe Salisbury/Harriet Dart (5pts)
Alicia Barnett 3-6 3-6 Maia Lumsden (3pts)
Ryan Peniston 6-7 6-3 10-12 Liam Broady (2pts)
Heather Watson 6-0 6-2 Beth Grey (2pts)
Dan Evans 7-5 6-2 Aidan McHugh (3pts)