He started at the Saints in 2018 as an assistant coach before being promoted to the top job the following year.
Ratten’s focus at the Kangaroos will with on the midfield.
The 51-year-old previously served as Carlton’s senior coach from 2007-2012 before joining Hawthorn as an assistant coach under Clarkson in 2013.
Ratten spent six seasons at Hawthorn, aiding during the club’s three successive premierships from 2013-2015.
“Brett comes to the club as an experienced, knowledgeable football person and we are thrilled to welcome him to Arden St,” North Melbourne’s general manager of football Todd Viney said.
“Brett is a highly regarded operator who has been part of premiership success during his time at Hawthorn. His vast coaching experience will be a huge asset for our club.”
Viney was hired at the expense of Daniel McPherson shortly after Clarkson’s arrival at Arden Street.
Adding to the upheaval, the Kangaroos also announced the departures of CEO Ben Amarfio and assistant coaches Heath Younie and Anthony Rocca at the conclusion of the 2022 season.
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