Randall had been in the position for six years after Evangelos Marinakis bought the club in 2017 and spoke about what an honour it is to take on the role once more.
“I would like to extend my thanks to Tom for his hard work and dedication over the past year and a half.
"During that time, it has been a privilege to have remained closely involved with the club as a member of the board, and I am delighted to resume the role of chairman today.
“I would like to thank Evangelos Marinakis and my fellow Board members for entrusting me with the position once again, and I look forward to the next exciting chapter in our history.”
Cartledge is set to focus on the running of his family business and opened up on the experience he has had working with such a huge Premier League side.
“I have had an incredible experience over the last 15 months, working for the club I love and have supported all my life.
“Over the last year and a half we have taken significant steps in securing the club’s future at an expanded City Ground and I will now continue to advise the owners on the real estate strategy whilst spending more time working in my family business."