Warning: SPOILERS for Star Trek: Discovery Season 3, Episode 3 - "People of Earth"

Star Trek: Discovery revealed that in the 32nd century, the Terran homeworld has reverted back to calling itself United Earth, which was its designation during the 22nd-century era of Star Trek: Enterprise. "People of Earth", episode 3 of Star Trek: Discovery season 3, saw the U.S.S. Discovery return home, only to be shocked to find Earth was no longer part of the United Federation of Planets and is now proudly on its own after voluntarily isolating itself from the rest of the galaxy.

In Star Trek's canonical history, Earth survived the Eugenics Wars and World War III in the 21st century, but the trajectory of Mankind changed irrecoverably when Zephram Cochrane (James Cromwell) successfully launched a warp-capable starship. This led to First Contact with the Vulcans on April 5, 2063, as seen in Star Trek: First Contact. With the Vulcans' help, the human race revolutionized life on Earth; within a hundred years, war, famine, poverty, and the accumulation of material wealth as the driving force of humanity were ended. Starfleet was established to explore strange new worlds and seek out new life and new civilizations. By the 22nd century, the Earth was overseen by a unified World Government and was known as United Earth.

Related: Star Trek: Discovery Season 3 Brings Back Enterprise's TOS Aliens

Starting in 2151, the pioneering voyages of the NX-01 Enterprise led by Captain Jonathan Archer (Scott Bakula) formed crucial alliances with races like the Andorians and the Tellarites. In 2161, Archer oversaw the formation of the Coalition of Planets, which became the United Federation of Planets, with Vulcan, Andor, Tellar, and United Earth as the core founding member worlds. The Federation expanded rapidly over the next two centuries, admitting hundreds of member worlds, and surviving several wars and threats from rival galactic powers like the Klingons, Romulans, the Borg, and the Dominion.

All throughout its membership in the Federation, Earth was still classified as United Earth but, because the Federation President's office was in Paris, France while the Federation Council, Starfleet Headquarters, and Starfleet Academy were based in San Francisco, California, United Earth became synonymous with the United Federation of Planets. Earth's solar system was designated Sector 001 and became the core system of the United Federation of Planets. As the center of the Federation and the nexus of intergalactic culture, technology, and politics, Earth became a paradise.

All of this stood for nearly a thousand years until the Burn, which happened sometime between 3068-3088 and caused the simultaneous explosion of dilithium across the galaxy. Starfleet was wiped out in an instant and the Federation quickly fell apart. But perhaps the most shocking outcome of all is that United Earth, fearful that the Burn was an attack on the UFP, decided to sever its membership in the Federation and banished it from the Terran homeworld.

Instead, United Earth asserted its independence, drafted a United Earth charter, and established the United Earth Defense Force to protect their homeworld from hostile threats like dilithium raiders, which includes a planetary defense grid and force field. As the UEDF's Captain Ndoye (Phumzile Sitole) explained to the crew of Discovery, United Earth decided to "focus on what we had..." and they "rebuilt the planet to become self-sufficient".

All of this brings United Earth full circle to its original status a thousand years ago during Star Trek: Enterprise's era. It remains to be seen if Commander Michael Burnham (Sonequa Martin-Green), Captain Saru (Doug Jones), and their crew can unite the wayward fragments of the Federation and coax United Earth to resume its rightful place as the center of the UFP in Star Trek: Discovery season 3.

Next: Star Trek: Discovery Season 3, Episode 2 Is A Proper TOS Throwback

Star Trek: Discovery streams Thursdays on CBS All-Access and Fridays internationally on Netflix.