On December 14, 2017, Brockhampton announced their fourth studio album, Team Effort, slated for release in 2018,^[2] but in March 2018, they announced that Team Effort had been delayed. On March 20, Kevin Abstract and other members posted a "work-in-progress" album cover of "PUPPY", scrapping the name "Team Effort" completely. "PUPPY" was set to be released some time in June.^[3] The next week, they announced via social media that they had signed a record deal with Sony's RCA Records in a deal reportedly worth $15 million for six albums over three years.^[4] PUPPY was also delayed (revealed on Kevin Abstract's Instagram Live) following allegations of sexual misconduct against founding member Ameer Vann.^[5][6] On May 27, Brockhampton announced via Twitter that Vann would no longer be a part of the group, and cancelled the remainder of their tour dates to regroup.^[7]

Following Vann's departure, on June 20, the band made their late-night television debut when they appeared on The Tonight Show Starring Jimmy Fallon performing a new song "Tonya", accompanied by guest vocalists Jazmine Sullivan, Ryan Beatty and Serpentwithfeet, as well as revealing the new title of their upcoming album, The Best Years of Our Lives.^[8][9] The next month the group announced a Beats 1 radio show Things We Lost in the Fire Radio,^[10] where they debuted a trilogy of singles, "1999 Wildfire", "1998 Truman" and "1997 Diana", released throughout July 2018.^[11][12][13]

The album was recorded over 10 days at Abbey Road Studios in 2018, with further recording taking place at the Brockhampton Factory in Hawaii.^[14] Kevin Abstract stated on Twitter that the album was inspired by English rock band Radiohead's fourth studio album, Kid A (2000).^[15]