In the early 18th century, traveling performers used trickery and manipulations of leverage to perform impressive-looking "feats of strength." These weren't real strongmen, per se, but rather normal dudes who had a slightly above-average understanding of physics. This all changed with Thomas Topham, a British man who managed to perform the feats without any shenanigans.
Topham lacked the craft or knowledge of the aforementioned "strongmen," but he was able to meet or exceed their feats due to his abnormal and actual super-strength. One notable exception was when he tried to pull against two horses. "Ignorant of the method, he seated himself on the ground with his feet against two stirrups, and by the weight of his body he succeeded in pulling against a single horse; but in attempting to pull against two horses, he was lifted out of his place and, one of his knees was shattered against the stirrups."
Because of this accident, Topham walked with a limp. He also stood an unassuming 5'10", so he hardly fit the profile of the world's strongest man. When he applied to perform his act in Devon, a local politician "requested him to strip, that he might examine whether he was made like them... was found to be extremely muscular. What were hollows under the arms and hams of others, were filled up with ligaments in him."
Topham was said to have done the following during his performances:
1. "Roll up a pewter dish of seven pounds as a man rolls up a sheet of paper."
2. " a pewter quart at an arm’s length, and squeez the sides together like an egg-shell."
3. "Lift two hundred weight with his little finger, and mov it gently over his head."
4. "Broke a rope fastened to the floor, that would sustain twenty hundred weight."
5. "His head being laid on one chair, and his feet on another, four people (fourteen stone each) sat upon his body, which he heaved at pleasure."
6. "He struck a round bar of iron, one inch diameter, against his naked arm, and at one stroke bent it like a bow."
7. "Having laid seven or eight short and strong pieces of tobacco-pipe on the first and third fingers, he broke them my the force of his middle finger."
8. "He broke the bowl of strong tobacco-pipe placed between his first and third fingers, by pressing his fingers together sideways."
9. "Having thrust a bowl under his garter, his legs being bent, he broke it to pieces by the tendons of his hams, without altering the bending of his leg."
10. "Dr. Desaguliers saw him lift a rolling stone of about 800 pounds’ weight with his hands only, standing in a frame above it and taking told of a frame fastened to it."
11. "Taking a poker, and holding the ends of it in his hands, and the middle against the back of his neck, he brought both ends of it together before him, and then pulled it almost straight again."
12. "He took Mr. Chambers, Vicar of All Saints, who weighed twenty-seven stone, and raised him with one hand."
(It should be noted that twenty-seven stone is 378 lbs. It seems that Mr. Chambers was the Vicar of All-You-Can-Eat, as well.)
All those feats were part of his act, but, while living his normal life in Islington, observers had seen Topham display his power by "breaking a broomstick of the first magnitude by striking it against his bare arm, lifting two hogs-heads of water, heaving his horse over the turnpike gate," and "carrying the beam of a house as a soldier carries his firelock."
Oh, and he also loved to sing. "I heard him sing a solo to the organ in St. Werburgh’s church," said one party, "though he might perform with judgment, yet the voice, more terrible than sweet, scarcely seemed human."
[Sources: The Spirit of the English Magazines; American Magazine of Useful and Entertaining Knowledge, Volume 3]