ANGERME (アンジュルム) originally formed in 2009 with four Hello!Project Egg members (three of four of the members were also previously in the anime group project Shugo Chara Egg!).

The group had a pre-debut under the name S/mileage (スマイレージ) with members Ayaka Wada (和田彩花), Yuuka Maeda (前田憂佳), Kanon Fukuda (福田花音) and Saki Ogawa (小川紗季) with the single aMa no Jaku in June of 2009. S/mileage was announced as a permanent group following three singles. Following this news, the group had their official debut with their fourth single オトナになるって難しい (It’s Hard to Be an Adult) on March 14th, 2010.

The group was seen as experimentative, with, often, out of the box, whacky concepts and themes; though this would change with the name change in five years, however, the group did start experimenting with more mature concepts in 2013, a few years leading up to the rebrand.

One year after, the group announced auditions for a second-generation lineup, which added members Akari Takeuchi (竹内朱莉), Rina Katsuta (勝田里奈), Kana Nakanishi (中西香菜), Fuyuka Kosuga (小数賀芙由香), and Meimi Tamura (田村芽実), while member Saki Ogawa (小川紗季) graduated from the girl group, citing her wishes to return to civilian life. Kosuga would be absent for an event due to anemia, but resumed activities after recovery despite leaving the group temporarily. Member Yuuka Maeda (前田憂佳) would also leave the group and the company in December of 2011, citing that she wanted to concentrate on her university entrance exams and that it would not be fair for her fans if she dedicated half her energy on idol work.

After five years of promoting as S/mileage, the group announced a sudden name change. This name was announced as ANGERME, as suggested by member Kana Nakanishi (中西香菜), and was to reflect on the new changes of the group with the addition of the third generation members. This includes Mizuki Murota (室田瑞希), Maho Aikawa (相川茉穂), and Rikako Sasaki (佐々木莉佳子).

In May of 2015, Kanon Fukuda (福田花音) announced her departure from the group, also citing her wishes to focus on university. Moe Kamikokuryou (上國料萌衣) joined the group the same year after auditions were held; she was the only one to be picked from the audition process.

A month after Kanon Fukuda (福田花音) graduated, Meimi Tamura (田村芽実) also graduated from the group and a fifth-generation member, Momona Kasahara (笠原桃奈), joined the group.

In 2017 and 2018, new generation members continued to join the group as Funaki Musubu (船木結) (a transfer from Country Girls) and Kawamura Ayano (a former Hello!Pro Kenshuusei trainee) joined the group, while Maho Aikawa (相川茉穂) took a hiatus from the group due to underlying health issues from panic disorder and would graduate from the group after being on hiatus for 12 months.

In the fall of 2019, two new members joined the lineup, which includes Ise Layla (伊勢鈴蘭) and Haruka Oota (太田遥香), marking the seventh-generation of the group. However, in May, leader Ayaka Wada (和田彩花) announced her departure from the group and the company, graduating in June of 2019, with Rina Katsuta (勝田里奈) following only days after. With the departure, eighth-generation member Rin Hashisako (橋迫鈴) joined the group. However, Kana Nakanishi (中西香菜) would graduate not long after.

Mizuki Murota (室田瑞希) and Funaki Musubu (船木結) would graduate from the group in 2020, while member Haruka Oota (太田遥香) has been suspended from participating in any activities due to rule violations, which went into effect in February of 2020.

As of 2023, the group is active with a total of ten members.