The world's tallest man ever recorded in the history of mankind - Robert Wadlow, was born in Alton, Illinois, in 1918, and was 6 feet tall by the time he was even eight years old. He suffered from the disorder Gigantism that makes the lower portions of the body extremely large, while the head and torso remain at normal sizes. This is caused by a pituitary gland tumor that excretes large amounts of growth hormone, resulting in the disorder that is technically called as acromegalic gigantism. He reached a final height of 8 feet 11 inches at the age of twenty-one years, and finally died of an inflamed leg.