Known across both hemispheres as the premier act supplying credits music for Japanese animated productions, the dance-rock outfit Flow earned widespread recognition through contributions to flagship series such as Naruto, Eureka Seven, and Code Geass. What began as an X-Japan cover project spent the greater part of the nineties clarifying its artistic direction and laying groundwork for later accomplishments. Brothers Koushi and Take launched the endeavor in 1993 first as Wyburn and subsequently as Pinking, advancing from X-Japan emulation through a phase centered on guitarist Hide before committing to original songs. Flow took definitive shape in 1998 with the addition of vocalist Keigo and bassist Got's, while drummer Iwasaki arrived in 2000; the group also adopted its permanent name and integrated rock with hip-hop and dance elements at that time.
Between 2000 and the middle of 2003 the band released five EPs and singles that generally charted respectably on Japanese independent listings, although Okuru Kotoba reached sixth place on the national charts. The debut full-length album Splash!!!, drawn from previously issued tracks, surfaced in 2003, climbed to number two, and secured a contract with Ki/oon, the same label that houses Asian Kung-Fu Generation. Their first major single, "Blaster," followed later that year, and the initial major-label album Game appeared in 2004, with Golden Coast arriving the next year. This period also marked the start of an intensive run of media placements that included Naruto tracks "Go!!!" in 2004 and "Re:member" in 2006, "Days" for Eureka Seven in 2005, "Colors" for Code Geass in 2006, and "Realize," which accompanied PS2 games adapted from Eureka Seven. Those placements produced Flow's earliest overseas appearance, performed for anime enthusiasts at Dallas' Anime Fest 2006.
The 2007 single "Answer" was chosen for the live-action Japanese drama Tantei Gakuen Q, while a further release, Night Parade, resulted from a collaboration with hip-hoppers Home Made Kazoku and was featured on the fourth studio album Airu, which reached seventh position on the charts in 2008.