Short answers, pulled from the story.
J-pop began in 1958 when forty-five thousand people attended the Nichigeki Western Carnival to see Japanese singers perform rockabilly music. This event marked a turning point when local artists like Kosaka Kazuya and The Wagon Masters started translating American songs into their own language.
Kyu Sakamoto's song Ue wo Muite Arukō became the first Japanese song to top the American charts in 1963. Known internationally as Sukiyaki, the track sold one million copies and spent four weeks on Cash Box and three weeks on Billboard.
Haruomi Hosono formed Yellow Magic Orchestra in 1977 after leaving the band Happy End. Their album Solid State Survivor reached number one on the Oricon charts in July 1980 and sold two million records worldwide.
Namie Amuro's 1997 single Can You Celebrate? sold 2.29 million copies making it the best-selling single of all time by a female solo artist in J-pop history. Her partnership with producer Tetsuya Komuro ended as she shifted toward contemporary R&B.
EMI Music Japan announced in October 2007 that Hikaru Utada was the world's first artist to achieve ten million digital sales in a single year through the Chaku-uta system. Her 2007 song Flavor of Life sold over seven million downloaded copies within that system.
AKB48 has occupied the top spot in the Oricon yearly single sales ranking every year since 2010 during the Warring Idols Period. Momoiro Clover Z attracted about 486,000 people to live concerts during 2014 which remains the highest recorded attendance for any female musician in Japan.