History
2010
On 10 July 2010, AKB48 first announced that they would be forming a second sister national group.[1] based in Namba.[2] NMB48 officially became active on 9 October 2010.]Yasushi Akimoto announced that the group would have 26 trainees for the first generation.These members made their first appearance at the AKB48 Tokyo Autumn Festival.
2011
NMB48 made their debut performance at their theater on New Year's Day 2011. They released their debut single, "Zetsumetsu Kurokami Shōjo", on 20 July 2011.In its debut week, the single sold a total of about 218,000 copies, making it the bestselling single on the Oricon weekly charts for the week of 20–27 July 2011.This makes NMB48 the second girl group after Passpo to reach number 1 with a debut single.
2012
On the first day of AKB48's Tokyo Dome Concert held on August 24, 2012, it was announced that AKB48 Team A member Yui Yokoyama would hold a concurrent Position in NMB48. Miyuki Watanabe of Team N would hold a concurrent position in AKB48 Team B. Also, Riho Kotani of Team N will hold a concurrent position in AKB48, Team A.
On September 3, Eriko Jo, a member of Team M, announced that she would be leaving the group during the performance at the theater.Her "graduation" performance was on September 28 at the NMB48 Theater. Following Jo's graduation, two members from Team M announced their resignation in early October. On October 9, three trainees were promoted to Team M to replace the members who had left. Fuuko Yagura became the new "center" member of Team M.
On October 10, sixteen third-generation trainees formed Team BII. On December 19, Yui Yokoyama was promoted to Team N.
2013
On April 18, 2013, first-generation member Nana Yamada was transferred from Team N to Team M, and trainee members Naruma Koga and Aika Nishimura were promoted to Team N.[10] At the AKB48 Group Concert in the Nippon Budokan on April 28, 2013, it was announced that Yui Yokoyama's concurrent position in the group would end, and that AKB48 Member Miori Ichikawa would have a concurrent position in Team N.
2014
In the AKB48 Group Daisokaku Matsuri held on February 24, 2014, major changes occurred to NMB48. Sayaka Yamamoto became a concurrent member of Team K. Miyuki Watanabe became a concurrent member of Team S, and was transferred from Team N to Team BII. Mayu Ogasawara was transferred completely to Team B, Nana Yamada became a concurrent member of Team KII.
