STU48

The formation of STU48 was announced in October 2016.[1]

Nana Okada and Rino Sashihara, the first two members of STU48

The application period for new members was open from January until February 5. AKB48 members Mayu Watanabe and Yuki Kashiwagi visited the governments of seven Setouchi prefectures (Hiroshima, Yamaguchi, Ehime, Hyogo, Okayama, Tokushima and Kagawa) between them to promote the auditions.[2]

On February 22, it was announced that Nana Okada of AKB48 and Rino Sashihara of HKT48 would be concurrent members of STU48, and respectively hold the positions of captain and theater manager.[3]

On March 19, 44 applicants who passed the auditions to become first generation members were introduced.[4] On March 31, STU48's first generation was formed with 31 members.[5]

In April, Setouchi Destination Marketing Organization (DMO), the tourism board of Setouchi Region, announced their support of STU48 in the forms of capital investment, business development support, and assistance in coordinating with local governments.[6]

The first music video from STU48, "Setouchi no Koe", was released in June 2017.[7]

On November 25, Rino Sashihara canceled her concurrent position to focus on activities with HKT48.[8]

On January 16, the variety show STU48 no Setobingo! (STU48のセトビンゴ！, STU48's Setobingo!. Unlike the other Bingo! shows, the title is customarily rendered in katakana instead of romaji), based on AKBingo! and hosted by the comedy duo Maple Chogokin, started airing on Nippon TV. It would run for 11 episodes.

STU48's first single, "Kurayami" (暗闇, "Darkness"), was released on January 31.

On April 14, STU48 theater manager Manabu Yamamoto revealed the ship that would be used for the STU48 theater and announced that it would start operating in summer 2018.[9] However, due to the 2018 Japan floods and other factors, the launch date would be delayed to spring 2019.[10][11]

In July, it was announced that their second single, originally planned to be released on August 29, was also postponed due to the floods. The new release date was later confirmed to be February 13, 2019.[12]

In October, the group announced the formation of five "extra-curricular" subunits. Besides performing music, each of these subunits would also focus on different types of activities.[13][14]

In November, the group was selected as one of the New Artists of The Year for the 60th Japan Record Awards, making them a candidate to win the Japan Record Award for Best New Artist. They are the first group in the AKB48 Group to earn the distinction.[15]

On December 25, the group released their first member guidebook titled Mirai Kouro (未来航路, Future Course).[16] On December 26, the music video for their second single title song, "Kaze wo Matsu" (風を待つ, "Waiting for the Wind"), shot as an uncut long take by quadcopter drone in Onomichi, Hiroshima, was released.[17]

On February 13, STU48 released "Kaze wo Matsu" in five versions. The bonus content included DVDs featuring the members modelling the real-life uniforms of Setouchi schools. First week sales reached 276,316 copies according to Oricon, doubling that of their debut single.

On April 16, the group's newly remodeled ship, the STU48-go, was officially launched in a ship commissioning ceremony at Hiroshima Port. The event was live streamed on Showroom and attended by Hiroshima Prefecture governor Hidehiko Yuzaki and other government officials. STU48 performed live in the shipboard theater for the first time that evening, with an original stage play titled "GO! GO! little SEABIRDS!!" produced by Nezumi Imamura.[18]

On June 2, in an episode of STU Imousu TV, the group's third single was announced to be released on July 31. The title song would be performed by all 29 active members and trainees (Fu Yabushita would be absent as she was on hiatus for health reasons), and each subunit would have their own songs.[19] The music video for the title song, "Daisuki na Hito" (大好きな人, "Beloved Person"), was released on July 2.[20]

On December 3, 24 new members joined the group as second generation trainees, or "research students" (研究生, kenkyūsei).[21] Their debut performance took place on the STU48-go on December 21 and 22.[22]

On January 11, STU48's second original stage play, titled "Bokutachi no Koi no Yokan" (僕たちの恋の予感, "Premonition of Our Love") and produced by then captain Nana Okada, was performed for the first time at the STU48 Theater on the STU48-go, docked at Hiroshima Port at the time. The play included the song "Teokure Caution" (手遅れcaution, "Missed Chance Caution") by =LOVE, an idol group produced by former STU48 and HKT48 member Rino Sashihara.[23] In several interviews, various members commented that the stage play was "interesting" and "difficult to express" since there are several songs with themes unfamiliar to the group, such as "queens and slaves" (dominance and submission) and yuri, but also a good learning experience.[24][25]

On January 18, during STU48's concert at Tokyo Dome City Hall, Nana Okada announced that she would step down as the group's captain and appointed Mitsuki Imamura as her successor and Akari Fukuda as deputy captain, but would retain her concurrent membership.[26]

On March 28, due to the COVID-19 pandemic, STU48's third anniversary celebration was held via live streaming on the video service Niconico. The fifth single was also announced to be released on May 27.[27]

On June 4, STU48 announced the renewal of the subunits, including the formation of sister subunits[28] to the existing ones for the second generation trainees.[29]

In July, STU48 launched the Setouchi Library, an "online salon" to learn and collaborate in projects related to the Setouchi Region with the group's members and subject matter experts.[30]

On December 1, Yura Ikeda and Nana Okada won the first and third places, respectively, in the 3rd AKB48 Group No. 1 Singer Contest (AKB48グループ歌唱力No.1決定戦, AKB 48 gurūpu kashō-ryoku nanbā 1 kettei-sen). Honoka Yano also ranked among the top 8 finalists.[31] Among the six member groups of the AKB48 Group, STU48 had the most members advancing to the finals with seven contestants: Yura Ikeda, Honoka Yano, Nana Okada (represented both STU48 and AKB48), Aiko Kojima, Arisa Mineyoshi, Mahina Taniguchi, and Sara Shimizu (dropped out due to health issues).[32] In an interview, Okada commented that the group's achievements in the contest could be attributed to many members having trained since childhood, naming Actor's School Hiroshima as one of the training grounds, and that singing abilities, while not essential for idols, would open many new opportunities for them.[33]

On January 15, STU48 performed a concert at Nippon Budokan for the first time, where they announced the release of their sixth single on February 17.[34]

Charming Trip leader Chiho Ishida and STU48 center Yumiko Takino promoting Setouchi tourism at Darma Persada University, Jakarta, Indonesia (2019)

The theme of "girls' journey" refers to literally visiting Setouchi tourism destinations and promoting them domestically and overseas[51] and exploring the world of beauty and fashion. They have their own travel-related television programs, such as STU48 no IttekimaSU! (ＳＴＵ４８の行ってきまＳＵ！, "STU48's We're Leaving!") on Shinhiroshima Telecasting[52] and STU48 Furusato Senden LABO (STU48 ふるさと宣伝LABO, "STU48 Hometown Promotion LABO") on Yamaguchi Broadcasting.[53]

These units promote Shikoku, one of Japan's five major islands, especially its less-known interesting places and activities.[54]

All members except Yuka Oki are Shikoku natives.

On November 15, 2018, Imamura and Kadowaki were two of the three 48 Group members (the third being Hijiri Tanikawa of AKB48) selected to become the lead performers for the "No Way Man" live performance in Best Hits Kayosai, replacing the members who transferred to IZ*ONE (namely Hitomi Honda of AKB48 and Sakura Miyawaki and Nako Yabuki of HKT48), after passing the dance audition held by Yomiuri TV.[55][56]

Fu Yabushita, leader of MiKER!

MiKER! is a merger between the former MC unit Setomaiku (せとまいく) and sports unit Seto 7 (瀬戸７). Kai and Shinano were members of both units.[57]

On November 3, 2018, Kai, Takino, and former Seto 7 member Maiha Morishita participated in the 38th Hiroshima International Peace Marathon.[58][59]

All members of this unit are concurrently members of other units.