By early 1979, Genesis had survived the departure of Peter Gabriel and Steve Hackett and even released And Then There Were Three as a three-piece. While his bandmates were focusing on solo albums, Phil Collins took off to Vancouver to try and save his marriage after his wife moved there with their kids. The marriage ultimately fell apart, and Collins returned to the UK with a bunch of song ideas. He gigged around with Brand X and worked on stuff for his first solo album, Face Value. In November of that year, the band reunited in the studio, rejuvenated by the break, and started work on Duke.
— たかぴろ (@bpfry495) January 16, 2017
After the break, the band found the album quite easy to work on, and it became their first UK #1 record.