With the release of their latest single “Masaka No Confession” in April, AKB48 has entered its milestone 20th anniversary. Centered by trainee Azuki Yagi, a member of the 18th generation, this song—led by newer members just a few years into the group—refreshes the legacy of this long-standing idol group with a pure, classic pop energy.

The coupling track for the single is a remake of their 2006 debut song, titled “Sakurano Hanabiratati 2025.” Its inclusion reminds us just how far AKB48 has come—from an unknown group two decades ago to one that played a key role in establishing the “Japanese-style idol formula.”

AKB48’s archetypal style not only paved the way for idols to be accepted into the J-pop mainstream, but also laid the groundwork for a boom of alternative underground idols in livehouses and regional scenes. In other words, modern Japanese female idol culture has evolved in direct response to the phenomenon of AKB48 and the wider 48 Group (a collective of idol groups produced by Yasushi Akimoto).

AKB48 launched in December 2005. At the time, the success of Morning Musume and Hello! Project had already sparked a resurgence of female idols in the mainstream, and the early 2000s saw the emergence of several groups with unique musical directions. For example, Folder5 (2000–2003), a eurobeat-driven group from Okinawa descended from the Amuro Namie and SPEED lineage, scored multiple hits. Other notable names included dream (2000–2017), who evolved into a core part of E-girls; Z-1 (1999–2003), a training group that launched national actress Aya Ueto; BON-BON BLANCO (2002–2009), who performed with Latin percussion as a band; and Harenchi Punch (2004–2009), known for their straightforward J-pop sound. Amuse Inc. also launched the trainee project BEE-HIVE, which produced groups like BOYSTYLE (2001–2007) and Buzy (1998–2006). Yet few of these groups achieved lasting success—and many faded out just as AKB48 began to rise.

Looking back, it’s apparent that many of these groups struggled to navigate the gap between the mainstream aspirations of J-pop and the real nature of teen idols, in a market where prejudice toward idols remained strong. AKB48, on the other hand, focused from the outset on the unique appeal of idols—prioritizing charm over technical skill. This unapologetic approach echoed that of Onyanko Club from the 1980s, a group also produced by Yasushi Akimoto. Drawing on his decades of experience across entertainment, media connections, and production insight, Akimoto guided the AKB48 project to success. Another crucial figure was choreographer Mayumi Natsu, who helped nurture Morning Musume and handled early dance lessons and choreography for AKB48.

Thanks to the input of such pioneers, AKB48 became a one-of-a-kind idol group with unmatched name recognition and commercial success.

That said, AKB48 remained a niche presence from 2005 to 2007. Their breakthrough came in 2008 with “Ōgoe Diamond,” their first single after switching record labels. Written by Yoshimasa Inoue—a precocious musician who had debuted as a teen in techno-pop band Cosmic Invention and become a songwriter in the 1980s—the song featured a bright, major-key rock arrangement that matched the group’s gritty, earnest vibe.

From that song onward, choreographer Anna Makino took over. A former solo artist in the 1980s and a member of SUPER MONKEY’S in the early 1990s, she went on to mentor talents like Amuro Namie and SPEED. Her dynamic choreography became a signature of AKB48, and with her work on “RIVER” (2009), the group earned their first No.1 on the charts. Their 2010 MV for “Ponytail to Shushu” went on to become the most viewed music video on YouTube in Japan that year.

One of AKB48’s key innovations was their use of a large roster—including trainees—combined with promotion events like selections and ranking announcements, turning internal competition into a drama that fans could follow. This documentary-like format built on what Morning Musume had done in its early years, but what made AKB48 stand out was the establishment of a permanent theater in Akihabara where they held regular performances for their core fans. In this sense, AKB48 could be seen as a hybrid of mainstream media-driven idols and independent underground idols.

Meanwhile, the 48 Group expanded its franchise model. In 2008, SKE48 was launched in Sakae, Nagoya. Jurina Matsui, who was just 11 years old when selected as the center for “Oogoe Diamond,” became a symbolic figure of this era.

Another group that deserves mention alongside early AKB48 is Idoling!!! (2006–2015), which was launched as part of the eponymous TV program. Its members, drawn from various agencies, brought strong personalities to the group. In 2009, the two groups even collaborated under the name AKBIdoling!!! with the track “Chu Shiyouze!” However, since Idoling!!! lacked an independent structure outside the TV show, their activities remained limited, and they gradually fell behind AKB48 in visibility and influence.

Still, with backing from a major TV network, Idoling!!! helped launch the “TOKYO IDOL FESTIVAL” in 2010—a massive event showcasing many female idol groups. Over time, TIF expanded into a key platform for Japan’s increasingly diverse idol scene, becoming a central force in what came to be known as the “Idol Warring States Period” of the 2010s.

Writer：Koji Dejima
Japanese music writer. Editor-in-Chief of the Tower Records Japan magazine “bounce”.