Sir Ron Lionheart sounds like the textbook example of this in his videos. He's so infectiously enthusiastic, you can't not smile while listening to him. Just read the comments on his videos.
There are an unusual number of US politicians with this reputation, possibly because the US has this reputation in general (Eagleland, Mixed Flavor). As Cracked put it, the Europeans treat the US as the guy they get drunk with and say, "This guy! He might be a bit crazy, but you know, he's all right."
Exhibit A vis-a-vis the real relationship between Europe and the US: this image (made after the Charlie Hebdo attack in January 2015).
Not to be outdone is Texas' own Lyndon Johnson. His 'Treatment' is legendary for its burly method and its high success rate.
Interestingly, Liu Bang, who founded the Han Dynasty of China was one of these, famously loving drink and fighting—and also being a really charismatic guy while drinking, leading barkeeps to pour him free drinks because of his positive effect on business. Despite this, Zhang Fei is more often remembered to be one.
Another English king, Charles II, also fits the trope: called the "Merry Monarch," Charles brought back color and, shall we say, joie de vivre back to England after years of stern Puritan rule. He loved a good joke (he's one of Britain's snarkier monarchs) and a good drink, had an obscene number of mistresses (producing many bastards with the surname FitzRoynote Including the ancestor of the captain of HMS Beagle who asked Charles Darwin to come along on the famous trip to South America), and was often rumored to have liaisons with men, as well (though he still had a soft spot for his wife Queen Catherine, standing by her side when she came under fire and when she became an Ill Girl). He also enjoyed the theater (something else the Puritans had banned), and the Restoration Comedy dates from the first decade or so of his reign.
Charlemagne was a giant by any standard of his day, a renowned warrior as much as a ruler, and oh yeah, he was so informal that when he wasn't holding court with more or less anyone willing to drink and eat with him, he was insisting they join him while he bathed so the festivities wouldn't be unduly interrupted. He was the least formal king ever; his court was a constant party at which state business would from time to time get handled. And then the King would say (paraphrasing), "Excellent! Now for the wine!"
Oliver Reed. He had a reputation for his whole career as a hard-drinking hell-raiser who bore scars on his face from a bar fight in 1962. He died of a heart attack at age 61, after a night of hard drinking in which he consumed 3 bottles of rum and beat 5 sailors at arm wrestling.
George Washington was this but as an avid social climber and aspiring gentleman, he worked hard to suppress his bruiser qualities.
Vikings. A favorite pastime during feasts was inventing short poems which either told about one's own accomplishments or insulted another as subtly and cleverly as possible. The proper way to answer such an insult was to counter it with a poem of your own. Someone pulling out a sword during such friendly banter was considered nothing but a brute, and as such not a proper viking.
Ernie "Turtleman" Brown Jr., as shown on the Animal Planet documentary show Call of the Wildman. A friendly, outgoing and highly energetic man known for his signature rebel yell and catching anything from snapping turtles to coyotes with his bare hands.
Babe Ruth was famous for his prodigious eating, drinking, and womanizing, but he was also a great lover of fun and capable of great humor—to say nothing of being the best ball player of his time, if not ever. He also seems to have been pretty good with kids—which makes a kind of sense, since he never properly grew up himself. He was, however, horrible with names, calling everyone "kid" (including Lou Gehrig, who was a great friend of his until Gehrig's mother fell out with Ruth's wife).
Charles Barkley was one of the biggest Boisterous Bruisers in the NBA. He was an aggressive and physical player and was involved in several altercations both on and off the court (including, most unfortunately, an attempt to spit on a heckler and hitting a little girl instead). He was also gregarious and talkative, making the NBA's "All Interview Team" almost every year he was in the league. When the Dream Team went to the Olympics in 1992, they were cautioned to stay in their hotel as much as possible due to death threats from terrorists. Barkley completely ignored these warnings and spent his evenings strolling around Barcelona, drinking and talking with the starstruck locals. When asked where his security was, he held up his fists and said, "This is my security."
Among tennis players, Boris Becker is known as one. It was specially noticeable whenever he played against Stefan Edberg.