Michael Andrew McKagan grew up in Seattle's largely working-class University District, the youngest of eight children born to Marie and Elmer "Mac" McKagan. He has been called "Duff" since toddlerhood, to which he once referred as "an Irish thing". Following his parents' divorce, his mother supported the family by taking a job as a medical stenographer. He was taught how to play bass by his brother Bruce, further developing his skills by playing along with the albums 1999 by Prince and Damaged by Black Flag.

In 1979, at the age of 15, McKagan formed the punk band the Vains, in which he played bass; they released the single "School Jerks" in 1980. During this time, he also played guitar in the punk band the Living, which opened shows for Husker Du and D.O.A., which developed a devoted following.  In 1980, McKagan joined the pop-punk band the Fastbacks as their drummer. He appeared on their 1981 debut single "It's Your Birthday", which was issued on guitarist Kurt Bloch's label No Threes Records, and on the song "Someone Else's Room", which was included on the Seattle Syndrome Volume One compilation album, also released in 1981.  In 1982, McKagan became the drummer for the hardcore punk band The Fartz, with whom he recorded several demos, five of which were included on their 1990 album You, We See You Crawling. After several line-up changes, The Fartz evolved into the post-punk band 10 Minute Warning, for which McKagan played guitar.  In 1983, McKagan moved to Los Angeles, California, with one of his brothers where he found work as an appetizer server at a Black Angus restaurant in Northridge. Answering an ad for a bass guitarist in a local newspaper, he met guitarist Slash and drummer Steven Adler, with whom he formed the short-lived band Road Crew. They auditioned a number of singers, including one-time Black Flag vocalist Ron Reyes, and worked on material that included the main riff of what would become the Guns N' Roses song "Rocket Queen". Slash eventually disbanded the group due to them not being able to find a singer, as well as Adler's lack of work ethic compared to himself and McKagan.

what role did he have?
he played bass;