1the9
South Korean boy band formed through Under Nineteen.
1THE9 (Korean: 원더나인, stylized as 1THE9, pronounced "Wonder Nine") was a South Korean boy band created through the 2018 survival show *Under Nineteen*. The group had nine members: Yoo Yong-ha, Kim Tae-woo, Lee Seung-hwan, Shin Ye-chan, Kim Jun-seo, Jeon Do-yum, Jung Jin-sung, Jeong Taek-hyeon, and Park Sung-won. The final lineup was announced on February 9, 2019, and the group was originally set to promote under PocketDol Studio for 12 months. Due to delays caused by the COVID-19 pandemic, they disbanded in August 2020.
The group formed through MBC's *Under Nineteen*, which aired from November 3, 2018, to February 9, 2019. Out of 57 initial trainees, viewers voted to select the final nine members, revealed live on television. Two hours after the broadcast, the members held a V Live to thank fans and announce their group name. Vocal team director Crush was later confirmed to write and produce their pre-debut track 'Domino'. Although their official debut was scheduled for April, the group performed at *Under Nineteen*'s Final Concert on February 23, 2019, alongside other contestants. They also promoted the pre-debut single "Like a Magic" on music shows.
On February 22, 2019, their official debut was set for April 12, with a concert later that month and a planned Japan debut. A reality show for the group began airing on March 22. Their Japan debut was postponed as MBK focused on South Korean promotions. Individual teasers were released before the debut timeline was announced. On April 5, the debut timeline began, revealing the album title *XIX* and lead single "Spotlight." A pre-debut track, "Domino" featuring Crush, dropped on April 7, followed by their official debut on April 13. They promoted *XIX* with "Spotlight" on music shows. On April 17, they held a debut stage via V Live, performing three songs, playing games, and announcing their fandom name (Wonderland) and color (Lime Punch). On October 3, 2019, a second mini-album, *Blah Blah*, was announced for release on October 17.
On July 6, 2020, a third mini-album, *Turn Over*, was announced for July 16. On July 27, 2020, the group's disbandment was confirmed for August 8. Before disbanding, they released a final EP, *Good Bye 1the9*, on August 5.
Members: Yoo Yong-ha (leader), Kim Tae-woo, Lee Seung-hwan, Shin Ye-chan, Kim Jun-seo, Jeon Do-yeom, Jung Jin-sung, Jeong Taek-hyeon, and Park Sung-won.
- formed
- 2018
- disbanded
- August 2020
- field
- K-pop
- nationality
- South Korean
- known_for
- Formed through MBC survival show Under Nineteen
- members
- 9
Quick Facts
- Landscape
- yes
- Origin
- Seoul, South Korea
- Genre
- K-pop
- Years Active
- 2019–2020
- Label
- PocketDol Studio
- Past Members
- Yoo Yong-ha / Kim Tae-woo / Lee Seung-hwan / Shin Ye-chan / Kim Jun-seo / Jeon Do-yum / Jung Jin-sung / Jeong Taek-hyeon / Park Sung-won
- Background
- group_or_band
Facts from the source article.
Lore & Background
1THE9 was formed through the survival competition series Under Nineteen, which aired on MBC from November 3, 2018, until February 9, 2019. Out of an initial 57 trainees, the final 9 were chosen by audience voting and announced via live television broadcast. During the final broadcast, the final members were ranked and marked to debut by votes from the fans. It was announced that vocal team director Crush would be writing and producing the group's pre-debut track 'Domino'. Although their official debut was scheduled for April, they participated in 'Under Nineteen's Final Concert' on February 23, 2019, performing songs from the show with other contestants. Since the show, the members performed the single 'Like a Magic' on music shows as a pre-debut promotion single.
On February 22, 2019, it was announced that their official debut was set for April 12 with a concert later in the month and
Reader's Guide
1THE9 represents a notable example of a project group formed through a survival competition, with a fixed 12-month promotional period under PocketDol Studio. Their formation through MBC's Under Nineteen, which aired from November 2018 to February 2019, followed the popular survival show format that had produced other K-pop groups. The group's timeline was affected by the COVID-19 pandemic, leading to delays and ultimately their disbandment in August 2020, slightly beyond their initial 12-month contract. Despite their short career, they released three mini-albums: XIX (April 2019), Blah Blah (October 2019), and Turn Over (July 2020), followed by a final EP Good Bye 1the9 (August 2020). Their significance lies in being a product of the survival show era, with a dedicated fandom called Wonderland, and their disbandment highlights the challenges faced by temporary project groups in the K-pop industry, especially during the pandemic.
Did You Know?
- The group's name 1THE9 is stylized as 1THE9 and pronounced as 'Wonder Nine'.
- Their fandom name was announced as Wonderland and their fandom color as Lime Punch during a V Live debut stage on April 17, 2019.
- Vocal team director Crush wrote and produced the group's debuting single.
- The group disbanded on August 8, 2020, after delays surrounding the COVID-19 pandemic.
Frequently Asked Questions
Who is 1the9?
1the9 (pronounced "Wonder Nine") was a South Korean boy group of nine members who debuted in early 2019 under PocketDol Studio. They were the final result of MBC's 2018 survival competition *Under Nineteen*.
How did 1the9 form?
The group was assembled through MBC's reality competition show *Under Nineteen*, which aired in late 2018 and had young male trainees compete for a place in the final lineup. The nine members who made the cut were officially announced on February 9, 2019.
Who were the nine members of 1the9?
The lineup consisted of Yoo Yong-ha, Kim Tae-woo, Lee Seung-hwan, Shin Ye-chan, Kim Jun-seo, Jeon Do-yum, Jung Jin-sung, Jeong Taek-hyeon, and Park Sung-won. All nine were selected together as the final group at the end of the survival show.
When and why did 1the9 disband?
The group officially ended their activities in August 2020, about a year and a half after debuting. Their original 12-month contract with PocketDol Studio was stretched out by the global pandemic, and the group ultimately disbanded once that extended period concluded.
Why is 1the9 notable in K-pop?
They are best remembered as the winning group from the high-profile MBC survival series *Under Nineteen*, which drew considerable viewer attention in 2018. Despite a relatively short active window, the show and the group's formation remain a recognizable part of late-2010s K-pop history.
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