31st century Earth; a real fixer-upper.
The 31st century is a one-hundred year period of time that spans the years 3000-3099. Since this takes place soooooo far in the future, obviously all references to 31st century in television fiction relate to the science fiction genre.
The 31st century is the central time era of the 1974 sci-fi series Planet of the Apes, which was based on the popular films series of the 1960s-70s. The opening credits of the show reveal Earth astronauts Alan Virdon and Peter Burke, who come from the year 1980, but are shunted through a time warp until they crash land back on Earth in the Southern California region in the year 3085. In the intervening 1,105 years, Earth has pretty much gone to pot. Global atomic warfare spelled the downfall of humanity and what survived fell victim to a growing culture of intelligent and aggressive humanoid apes. By 3085, these anthropomorphic apes are the dominant life form on the planet. However, their technological level is that of a bygone era. No phone. No lights. No motor cars. Not a single luxury. Like Robinson Crusoe (or Gilligan's Island), it's as primitive as can be.
Upon arriving on this topsy turvy future reality, Virdon and Burke are befriended by a chimpanzee named Galen, but quickly discover that he is one of the only apes in Central City, that doesn't look down their nose at humans. The authoritative body of the region is governed by a council led by an orangutan named Zaius, who enforces his order through his military commander, General Urko.
Humans in the 31st century reality of Planet of the Apes are more intelligent than they were presented in the 1968 film Planet of the Apes, but they are considered a lower form of life, and serve as indentured servants (if not outright slaves) to the apes.