Oneus, pronounced "one us," debuted in January 2019 as the first boy band from the entertainment company RBW, home to the girl group Mamamoo.
Oneus is the "brother" band of Onewe, pronounced “one we,” which debuted just four months after. The two bands are nicknamed Weus, pronounced “we us,” by the fans.
The two bands were put together through a project titled "RBW Debut Project 'I Shall Debut'" in November 2017, from which the agency disclosed monthly assessments, tests and evaluation content online. An online show with the same title took place in July 2018, helping the bands garner a steady fan base even before their official debuts.
Oneus has been famed for its traditional Korean concept, evident in songs like "LIT" (2019) and "LUNA" (2021), using traditional sounds, attire and dance moves in the songs. All members are also Korean, which has become uncommon in fourth-generation K-pop.
Oneus went on its first U.S. tour in November 2019, followed by its second U.S. tour in February 2022. It began its first world tour, "REACH FOR US," in October 2022, followed by performances in Japan, the United States, Puerto Rico, Mexico, Chile and Brazil.