Brown, 23, has joined for an undisclosed fee and has signed a three-year deal with Town, with his signing following on from the addition of former Aston Villa defender Tommy Elphick.
Chief executive Julian Winter, who says that the club are targeting five new signings this summer to boost their numbers, said: “We are hoping to do two (signings) before the end of the week and two into next week.
“We are looking at the loan window and getting creative with a couple of Premier League clubs as we did last time we were in the Championship and that served us really well.”
On Brown, head coach Jan Siewert added: “He is a very interesting player. He had a setback in his career when he left Birmingham City, but he showed great desire to go on and have a real impact at Forest Green Rovers.
“Now wants to show that he can apply his qualities to be a success in the Championship.”
Meanwhile, Rotherham United forward Jerry Yates has joined Swindon Town on a season-long loan.
Everton’s Dominic Calvert-Lewin is taking inspiration from Liverpool’s Champions League heroics in a bid to save England Under-21s’ Euro 2019 hopes.
The striker will start in Friday’s must-win Group C game with Romania in Italy after being a substitute in the opening defeat to France.
Former Sheffield United forward Calvert-Lewin said: “There is no better time to be an English footballer in my opinion, playing in the Premier League especially.”