Mawr, a planet classified as a gas giant, existed within the Tython system, situated in the Deep Core region of the galaxy. This celestial body had a retinue of seven moons. The settlers of the Tython system collectively called Mawr and Obri—another gas giant in the star system—"the Giants." Over 36,000 years prior to the Battle of Yavin, the settlers of Tython, who were not Force-sensitive, established colonies on the moons orbiting Mawr. By 25,793 BBY, facilities for gas mining had also been constructed within the atmosphere of the planet itself.
Within the Deep Core region of the galaxy, at grid coordinates L-10, resided Mawr, a planet of the gas giant type, located in the Tython system. This planet orbited Tythos, its sun, in the tenth orbital position, and was in turn orbited by seven moons. The Tython system's settlers referred to Mawr and Obri, which was also a gas giant and the ninth planet in the star system, collectively as "the Giants."
More than a millennium after 36,453 BBY, when the non–Force-sensitive settlers of Tython—the system's fifth planet—traveled to nearby worlds, they established colonies on Mawr's moons. By the time 25,793 BBY arrived, facilities for gas mining had also been established inside the planet's atmosphere. In that same year, Ketu, a Temple Master from the mystical Je'daii Order, recounted the history of the Tython system to Padawan learners Harun and Resi, mentioning the colonization of Mawr's natural satellites among other occurrences.
During the Rakata Infinite Empire's Invasion of the Tython system, their forces launched attacks on the moons of Mawr and Obri after the initial assault on Furies Gate. After seizing control of the gas giants and enslaving the inhabitants, they shifted their focus to Tython, but were forced back to Ska Gora.
The first depiction of Mawr appeared in the Tython entry within The Holonet feature of the official website for Star Wars: The Old Republic, a massively multiplayer online roleplaying game developed by BioWare that was released in 2011. A schematic of the Tython system showcased the gas giant. Since its creation in 2008, The Old Republic's website has undergone several revisions, leading to the removal of certain features and images, including the aforementioned schematic. Star Wars: Dawn of the Jedi 0, a preview issue of the Star Wars: Dawn of the Jedi series of comic books, provided Mawr's name and additional details. This issue, penned by John Ostrander and illustrated by Jan Duursema, was released on February 1, 2012. The planet was also mentioned in the first issue of the series, published on February 15 of that same year.