Napoleon Bonaparte had plenty of enemies, even on his deathbed in the Longwood House. The Longwood House is located on St. Helena, a small, extremely remote island that is over 1,200 miles away from any other landmass. This remoteness made the island a very popular location for exiling difficult people, and it's quite possible that nobody was more of a difficult person than Napoleon Bonaparte. There were numerous people who wanted him dead, from his house staff that he repeatedly angered through small provocations to the island's British governor to political adversaries. Some believe his death was caused, not by his enemies, but rather by the house in which he lived while exiled.
After his defeat, Napoleon Bonaparte was exiled by the British to the island of St. Helena. Napoleon's final years were spent writing his memoirs at Longwood House, while complaining about the damp environment and the quality of his keepers and living conditions. The Longwood House was chosen particularly for the remoteness of it on an already extremely remote island, due to Napoleon's reputation for coercion and escape. Hudson Lowe, his custodian, was not going to allow Napoleon to attempt an escape on his watch. There were several escape plots throughout Napoleon's years on St. Helena. Most of these were complicated, such as submarines, and unrealistic plots that were thought up by supporters located far away. None of these plots, however, came to fruition.
Napoleon's health began to decline by February of the year 1821. He was dead by May 5 of the same year. According to the autopsy, the official cause of his death was stomach cancer. Since Napoleon's death, many wild theories of accidental death and assassination have flourished. The most famous theory of all is the possibility that his death was a result of "poisoning by wallpaper." The idea is that the combination of the house's green wallpaper, Napoleon's habit of secluding himself inside the house to avoid his keeper' watchful eyes, and the damp environment may have become a deadly combination for the emperor.
The star-patterned, green wallpaper that's shown in representations of Napoleon Bonaparte on his deathbed apparently featured the popular at the time color called "Sheele's Green," which was a dye used to create a bright green hue. This dye also, as so happens, to off-gas fatal arsenic vapors when it's damp. Strands of Napoleon's hair were tested using modern methods, and the results showed them to contain suspiciously higher levels of arsenic. However, as interesting as the possibility was, recent studies have proven that the theory is nearly certainly untrue. Tests have shown that the hair from almost everyone from that era contained elevated arsenic levels because of continuous exposure to all kinds of toxic items that were commonly used during that time.
The original gravesite of Napoleon and the Longwood House today are maintained by the French government as historic sites. A large amount of the house has since been reconstructed due to termites and the damp environment's long-term effects. The green, arsenic wallpaper was replaced some time ago with a replica.