*edit*
there are dozens of martial artists I would love to train with ranging from Choki Motobu to Ip Man to Royce Gracie to Choy Hong Hi but if I had to pick one it would be James Fig.
he was the first champion of boxing in 1721 when it was a very different style where people would punch, kick, elbow, knee, headbutt, open hand strike, throw, trip, joint lock, choke & ground fight.
there were no rules back then and peoples groins were torn off and their eyes were poked out.
he was also a great swordsman and quarterstaff fighter and he was a soldier too who honed his skills on the battlefield.
he also taught most of the prominent boxers & swordsmen of his time in England.
there was an old story circa 1700s about the old British ways of fighting and it goues somthing along these lines-
"an old britt walked into town with his eye hanging from his face and I said oh my sir your eye is out! and he said if you think that is bad you should see the other rascal and presented to me a fresh pair of bullocks and then we went to the pub for a few pints"