Some amazing tales of real people have been brushed aside where maybe they shouldn't have been.
A fine example that's recently become widespread in popularity is the genius of Nikola Tesla. While never being called unimportant, he's recently come to prominence as arguably the most important inventor since they guy who made the wheel, to the evolution of human civilization. I think it would make a great TV series, him trying to out wit, Edison the obvious antagonist in that story. A wonderful tale from those two that I heard recently was that Nikola was asked, while working for Edison, to make his DC generator more efficient saying that if he did so, "He'd win the 50,000$ dollar prize." A phrase that from some research seems to be the equivalent today of, "If you build a better mouse trap the world will beat a path to your door." or "That's the 64,000$ dollar question." Nikola after accomplishing this (the same design still used to this day mind you) asked for his 50,000$ to which Edison replied, "You don't understand American humor." and gave him a small raise. After this he quit and went to work at manual labor for a time. All this I heard a while ago, the part I didn't was that he was digging ditches, and those ditches were for Edison power cables. It did have a happy ending as he met a friend of Westinghouse while there who was a foreman, who overheard him talking about the inferiority of DC to AC (a topic that put him on Edison's bad side from nearly day one of their working relationship) among the workers, he then introduced the two of them. What a story arc.
A second that I would love to see is that on Bartholomew Roberts, by far the most successful pirate of the Golden Age, having captured over 400 ships. His story began as a mate on a British ship in the East India Trading Company in the 1700's. While beset by pirates he was Shanghai'd into service to which they soon realized he was an excellent navigator, making him instantly worth his weight in gold and was consulted heavily by the captain. Though he didn't want to be there and held the pirates in contempt, viewing himself far superior in every sense of the word, he slowing started to see the benefits of money and power to be gained without much work. Soon after his enthrallment, the pirate captain was ambushed and shot on his way to have dinner with a Governor, since they were found out to be pirates. The crew being captain-less had to then take a vote on the next one to take charge. Roberts was near unanimously voted in as captain only six weeks after being taken hostage. He decided that his first act had to be a bold one so he decided to put the city that killed the old captain to the torch. They killed most the male inhabitants and stole everything they could find of value, all without a single causality. This first raid solidified the crew to his leadership. He then left a bloody trail across the Atlantic for two years being all but invincible.
These are the two TV series I'd like to see on true people, would love to hear some others you all think deserve to be made into shows or movies.