In 1984, Davey Boy and his partner, Dynamite Kid (The British Bulldogs) joined the WWF and began a long running feud with Hart and Neidhart, who were now known as The Hart Foundation.
The Bulldogs also feuded with the Dream Team (Greg Valentine and Brutus Beefcake). At WrestleMania 2, with "Captain" Lou Albano and Ozzy Osbourne in their corner, the Bulldogs defeated the Dream Team for the Tag Team Championship. The Bulldogs held the titles for nearly nine months, feuding with the Dream Team and Nikolai Volkoff and the Iron Sheik.
In January 1987, the Bulldogs lost the titles to the Hart Foundation, in kayfabe due to biased referee Dangerous Danny Davis (and in reality due to a severe back injury to the Dynamite Kid). Shortly before losing the titles, the Bulldogs gained a mascot, an actual bulldog who went by the name Matilda, and feuded with the likes of The Islanders (who, kayfabe, dog-napped Matilda), Demolition, and The Fabulous Rougeau Brothers.
The Bulldogs left the World Wrestling Federation in 1988.
In 1990, he returned to the WWF. Smith was pushed as the same character from the British Bulldogs' original WWF run, but this time as a singles star under the name The British Bulldog, and was much bigger in terms of muscle mass than he was in his first WWF run. He was a fairly popular wrestler in the United States, but was a huge attraction to fans in the United Kingdom, due in part to the WWF becoming a ratings hit on Sky Sports, as well as the promotion touring the country holding supercards such as UK Rampage which saw Smith defeat The Warlord at the London Arena in March 1991 and the Battle Royal at Royal Albert Hall in which Smith won a 20-man battle royal by eliminating Typhoon on October 13, 1991. After entering as the first man in the 1992 Royal Rumble, he eliminated "The Million Dollar Man" Ted DiBiase, Jerry Sags, and Haku before being eliminated by eventual winner Ric Flair.
Smith again headlined the WWF's European tours at European Rampage, winning a 15-man battle royal by eliminating The Mountie in München, Germany on April 14, 1992 and defeated Irwin R. Schyster in Sheffield, England on April 19, 1992.
In 1992, due to this newfound popularity, the WWF decided to hold its annual SummerSlam pay-per-view in Wembley Stadium. The show was main-evented by Smith (led to the ring by the British Heavyweight Boxing champion Lennox Lewis) and Bret Hart in a match for Hart's Intercontinental Championship. Initially, Hart was to lose the title to Shawn Michaels, but Hart suggested that Smith get the win at Summerslam as it would mean big business in England. On August 29, at SummerSlam, in front of 80,355 of his countrymen, Smith won the Intercontinental Title in a match which is regarded by many wrestling experts as the finest in his career. Smith lost the title to Michaels on the November 14 edition of Saturday Night's Main Event.
Smith's WWF run came to an end when he was released in 1992.
Smith returned to the WWF at SummerSlam 1994, as a spectator with the rest of the Hart family. Smith immediately became involved in an ongoing family feud between Bret Hart and his brother, Owen Hart. Smith teamed up with Bret against Owen and Jim Neidhart in a series of tag team matches.
Smith appeared at the 1994 Survivor Series in a 10-man elimination match. His partners were WWF Intercontinental Champion Razor Ramon, 1-2-3 Kid, and The Headshrinkers. They faced Tag Team Champions Shawn Michaels and Diesel, Owen Hart, Jeff Jarrett, and Jim Neidhart. Smith was eventually counted out, but his team won the match after the entire other side was counted out while trying to stop Diesel and Michaels from fighting in the back.
After entering the Royal Rumble as the second entrant, Smith and Shawn Michaels were the final two at the end. Smith tossed Michaels over the ropes and celebrated on the second turnbuckle. However, only one of Michaels feet hit the floor and he was able to reenter the ring, and eliminate Smith from behind, whilst Smith's music was playing and he was celebrating on the turnbuckles. Soon after, Smith began teaming with Lex Luger as the Allied Powers. The team wasn't much of a success and only wrestled on two pay-per-views as a tag team. The first came at WrestleMania XI were they defeated The Blu Brothers. The second came at In Your House 2 were they lost to Tag Team Champions Owen Hart and Yokozuna in July. Afterward the team briefly began feuding with Men on a Mission. During this time, Smith began teasing a heel turn at several live shows where he walked out on Luger during several of their matches together. Another incident saw him antagonize fans for chanting "USA" during their matches together, as they often had done. The normally affable, happy-go-lucky Smith became bitter and spiteful, and would get easily annoyed with the fans and his partner.
On the August 21 episode of Monday Night Raw, the Allied Powers were supposed to face Men on a Mission but Luger (kayfabe) no-showed the match; Smith found a replacement in then-WWF Champion Diesel. During the match, Smith completed his heel turn and attacked Diesel, assisting Men on a Mission in beating down the champion. He left the ring with manager Jim Cornette and joined former adversaries Owen Hart and Yokozuna in Cornette's stable. Upon turning heel, he changed his look by cutting his hair short, and developing a mean streak. Smith defeated Bam Bam Bigelow at In Your House 3. Later that night, he took Owen Hart's place in the main event, teaming up with Yokozuna to wrestle Shawn Michaels and Diesel in the Triple Header match, where all three championships were on the line, but lost when Diesel pinned Owen Hart who interfered. Weeks later, Smith redeemed himself by pinning Diesel in a six-man tag team match on RAW to earn a WWF title shot.
Smith received a WWF Championship shot against Diesel in the main event of In Your House 4 in Winnipeg, Manitoba. Smith won by disqualification after Bret Hart interfered. At the Survivor Series in Landover, Maryland, Smith participated in the Wild Card eight-man elimination match. He teamed with Shawn Michaels, Ahmed Johnson, and Sycho Sid. They faced WWF Intercontinental Champion Razor Ramon, Dean Douglas, Owen Hart, and Yokozuna. Smith, Michaels, and Johnson were the survivors.
In the main event of December's In Your House 5 from Hershey, Pennsylvania, Smith was granted a title shot against new WWF Champion Bret Hart in a rematch from their SummerSlam match back in 1992. They had another well-received match, yet Hart won this time.
Smith entered the 1996 Royal Rumble, where he made it to the final four before being eliminated by Shawn Michaels. At In Your House 6, he lost to Yokozuna by disqualification after Vader interfered. At WrestleMania XII, he teamed with Vader and Owen Hart to defeat Yokozuna, Ahmed Johnson, and Jake "The Snake" Roberts. At In Your House 7 in April, Smith and Owen Hart defeated Johnson and Roberts after Smith forced Roberts to submit.
In 1996, after Shawn Michaels became WWF Champion, Smith was put in a feud with the new champion. The feud was supposedly based on Smith's wife, Diana, accusing Michaels of hitting on her, which made Smith mad and determined to take the title from Michaels. The two main-evented the In Your House 8 pay-per-view, and their match ended in a double pin when Michaels German suplexed Smith and both their shoulders were counted down by separate referees. A rematch between the two headlined the 1996 King of the Ring pay-per-view. Michaels ended up successfully defending the title.
Afterwards, Smith formed a tag team with his brother-in-law, Owen Hart, and the two soon won the Tag Team Titles from The Smoking Gunns. The team defended their titles against teams such as Doug Furnas and Phil LaFon, Vader and Mankind, and The Legion of Doom.
In 1997, the WWF created the European Championship and Smith became the first ever holder of the title, winning a tournament in Germany, which culminated in him defeating his own tag team partner, Owen Hart in the finals, which made Smith a double champion.
Hart and Smith later joined forces with Bret Hart, Jim Neidhart, and Brian Pillman to re-form the Hart Foundation as a villainous faction which feuded with Stone Cold Steve Austin and other American wrestlers. This created a rift between American fans, who despised the Hart Foundation, and Canadian fans, who revered the Hart Foundation. Smith and Owen dropped the Tag Team Titles to Austin and Michaels, and lost the final match in a tournament for the vacant Tag Team Titles to Austin and Dude Love. Smith then started a feud with Ken Shamrock for the European Title, and eventually lost the European Title to Shawn Michaels in the main event of One Night Only. Smith was booked to successfully defend the belt against Michaels. However, Michaels convinced Vince McMahon that he should win, as it would create build-up not only for his impending rematch with Bret Hart, but also for a rematch against Smith at the next British pay-per-view. Smith reluctantly agreed, and fans at the event, who gave Smith an ovation, voiced their displeasure by booing Michaels and littering the ring with garbage. This marks the only time Smith lost on a WWF card in the United Kingdom, and the third championship Smith has lost to Shawn Michaels. After the events at Survivor Series 1997, Smith, along with Bret Hart and Neidhart, left the WWF.
Smith returned to the WWF in September 1999 following the death of Owen Hart in an in-ring accident. In keeping with the company's new "Attitude era", Smith began wrestling in jeans instead of his usual Union Flag-adorned tights and his theme music was changed from "Rule, Britannia!" to a remix of that particular theme, and later to rock music (complete with the sounds of a dog barking as the song began) that the WWF used for most of its talent at the time. On the September 9 episode of SmackDown! in Albany, New York, Smith defeated The Big Boss Man for the Hardcore Championship. Smith forfeited the title giving the belt back to Al Snow because Boss Man had previously (kayfabe) dog-napped Snow's dog Pepper to win the title from him, driving him insane in the process. Smith then began pursuing the WWF Championship, eventually turning into a villain and beginning a feud with The Rock. Smith headlined Unforgiven as part of a six-man WWF Championship Match that was won by Triple H. On October 2, Smith returned to England as a heel at Rebellion, where he defeated X-Pac. He lost to The Rock at No Mercy later that month.
Smith defeated D'Lo Brown for the European Championship on SmackDown! on October 26. It was also around this time he formed an alliance with the Mean Street Posse. He lost the title to Val Venis in a triple threat match at Armageddon on December 12 in Fort Lauderdale, Florida.
On May 6, 2000 in London, Smith defeated Crash Holly for the Hardcore Championship. In one of Smith's last televised appearances, Holly regained the title from him in New Haven, Connecticut on the May 11 episode of SmackDown!. His last televised match with the WWF was on Sunday Night Heat some weeks later, when he burst into Eddie Guerrero and Chyna's locker room, accusing Guerrero (who was the European Champion at the time) of not treating the belt with the respect it deserved. This led to a title match on Heat, in which both men were disqualified. On May 27, Smith defeated Steve Blackman in a house show in what would be his final match in both the WWE and his career. He was released from the company in early 2000.
Smith died on May 18, 2002.