The Class-M homeworld of the humanoid Bajoran race is Earth-like in appearance with large, blue oceans and seas that appear a little more greenish than Earth's from orbit. A "day" is a 26-hour rotation on its axis, and it has at least five moons, although two may be rogues.

It takes its name from the star of the system and is located close to the first known stable wormhole, discovered in 2369. Long before, however, ancient solar-sail craft harnessed its eddies and journeyed to the nearby Cardassian system, then much less advanced than Bajor.

The entire planet, or at least its largest continent, is known by geographic areas such as the Northwestern District, Northeastern District, etc. These districts in turn are composed of provinces such as Tozhat, Musilla, Hedrikspool, Dahkur, Lonar and Rakantha.

Bajor's territory also extends to outposts on other nearby worlds and along the Cardassian border, such as Dreon VII; the first Bajoran colony in the Gamma Quadrant, New Bajor, was reported to be maturing by stardate 47879.2 until violent plasma storms in the Denorios Belt cut off communications.

Though boasting an ancient and highly spiritual people whose culture flowered with arts and sciences long before such development on Earth, the planet's resources and pride were plundered by occupying Cardassians from 2318 to 2369, until decades of underground resistance finally forced the withdrawal; it had been annexed outright in 2329. While Bajoran underground cells fought for freedom during the Occupation and its religious orders were persecuted, the University of Bajor and institutions such as the Bajoran Center For Science remained open, and natives were allowed to maintain technical, scientific and clerical jobs and training, Many Bajoran data banks survived intact and functional.

The nearby wormhole and its non-linear alien builders are worshipped as the Prophets by the natives, especially after contact devices called Orbs were discovered. Bajor cemented a relationship with the Federation by inviting Starfleet administration of Terok Nor, the onetime Cardassian slave-labor mining and processing station in orbit. It was renamed Deep Space Nine and moved near the wormhole to protect it. DS9 is now about five hours away from Bajor by native transport, though only about three-hours away by runabout.

Its petition for UFP membership was finally approved circa stardate 50350, only to be postponed at the Emissary's warning not to join yet; indeed, Cardassia reoccupied the station in late 2373 as a Dominion client state after Bajor declared a non-agression pact with both for its own self-survival. Bajor has also dealt with recent tensions involving Klingons and the Maquis rebels. While not yet a Federation member, Bajor boasts several natives in Starfleet, including the missing Sito Jaxa and the now-renegade Ro Laren; others are in the Academy.