Which rapper's 2015 album 'To Pimp a Butterfly' was a critical and commercial success?

The rapper whose 2015 album To Pimp a Butterfly was a critical and commercial success is Kendrick Lamar.

Released on March 15, 2015, the album was Kendrick Lamar’s third studio album and followed his acclaimed 2012 breakthrough, Good Kid, M.A.A.D City. It blends hip-hop with jazz, funk, soul, and spoken-word elements, while addressing racial inequality, depression, identity, fame, and institutional discrimination.

To Pimp a Butterfly debuted at No. 1 on the Billboard 200 after selling 324,000 copies in the United States during its first week. It later surpassed one million U.S. copies and earned platinum certification. Critics praised its ambitious musical scope and political writing; the album won Best Rap Album at the 2016 Grammy Awards and received an Album of the Year nomination.

The title can be confused with Lamar’s later album DAMN., released in 2017, or with Kanye West’s similarly influential 2010 album My Beautiful Dark Twisted Fantasy. The featured single “King Kunta” is associated with the album, but “i” was its major award-winning single.