Nikola Tesla has been making quite a comeback over the past decade. Famed for his inventions, which pretty much make up the modern power grid, he has become an untouchable golden boy of all we expect a scientist to be. However, as always, the truth is a little more complicated.
It goes without saying that Tesla was a genius, for gods sake, the man could do complicated calculus in his head. However, being a genius doesn't always mean as much as you think. Tesla started his life as a Serbian immigrant who was brought to the US to work for the Thomas Edison Company, a company he had worked for previously in Europe installing electric lights. Tesla only worked for Edison for six months before quitting over, as he claimed, unpaid bonuses, which seems a little strange given that the amount he claimed Edison had cheated him out of was more than the company had. Anyways, soon after Tesla began toying around with generating electricity via AC generators, rather than the commonly used DC generators of the day (the difference is not really important to this story). This work led to numerous patents which Tesla licensed to the Westinghouse Electric Company, kicking off what became known as the War of the Currents as Westinghouse and Edison vied over who's preferred method, AC or DC, would power the world. Edison electrocuted an elephant to prove some kind of point and AC eventually became the dominant method, though none of this was important to Tesla beyond the fact that it made him a shit ton of money.
Suddenly independently wealthy, Tesla built himself a large laboratory and began living a very lavish lifestyle. It was the height of his career. Rich men threw money at him to fund his ideas and he was considered a media darling. He was the perfect quirky scientist, an extravagant celibate showman who claimed to only sleep two hours a night. At first Tesla's work concentrated on further development of AC power, which while boring, ensured a steady stream of capital. However, over time he increasingly got involved in other random areas of interest; including x-rays and radio remote control, neither of which led to much actual inventing other than a remote control boat. These side interests eventually gave way to an obsession over the idea of wireless power transmission, a compulsion that would end up driving Tesla to his ruin.
Tesla's obsession with wireless power began with his invention of the Tesla Coil, a device that created lightning but little else, and some cute demonstrations of how he could light a lightbulb without any wires. Thanks to these early somewhat successes, Tesla became convinced that he could use either the Earth itself or the atmosphere's ionosphere to transmit electricity and communications around the world. All he needed was a generator big enough. Using millions of dollars from rich investors he built giant towers, first in Colorado and then in New York, to conduct his experiments, which mostly involved bigger and bigger Tesla Coils. Not one of the experiments worked, probably because his theories on the subject were complete garbage, and before long his investors abandoned him. It was at this point that Tesla's financial difficulties began.
It goes without saying that such a turn of fortune resulted in Tesla having a complete nervous breakdown. A situation that was not helped by the fact that Tesla was severely sleep deprived. Despite his financial difficulties he refused to stop living his lavish lifestyle, one that became harder to continue as his various patents began to run out. With what few inventions he did create failing to catch on, a desperate Tesla sued the inventor of the radio, Guglielmo Marconi, for patent infringement, since you know, Tesla had once invented a radio controlled boat and all. However, the case ended up going nowhere. Almost completely broke, Tesla spent the remainder of his life getting kicked out of numerous hotels, for not paying his bills, and walking to the park everyday to feed the pigeons, one of which he was convinced was in love with him. During this period he made many claims of possible inventions, some of which would later prove to be correct; such as radar and an airplane that could take off vertically; and others that were not correct at all; such as wiring classrooms to stimulate children's minds with electricity. As he got older his claims became wilder with little to no proof to back them up; such as his invention of a deathray, earthquake machine, an entirely new theory of physics, and a thought camera. He died alone, nuttier than a fruitcake.