The 20 year-old defender has finally completed his move officially after MillersMAD first ran the story last Wednesday when Brown took up pre-season training with his new team mates.
And he told Millersplayer he was happy to be here after turning down a new contract at Portman Road and wants regular first team football.
"I'm pleased to come to Rotherham and I want to get the team promoted then the club will grow and hopefully I'll grow with them as a player as well. I had a great time at Ipswich and personally had a good season but I felt that it was time for me to move on and get regular football.
"I need games under my belt to learn and grow and gain experience and I don`t think there is a better place to do it than here. It will stand me in good stead having played games in the Championship last season."
Brown and boss Andy Scott link up after Brown's days at Fulham when he was just a young boy, and he added: "I think Andy Scott is a top man. I enjoyed our chat and he definitely made the club sound good in my eyes and that`s why I`m here.
"Hopefully I can prove to everyone that I'm worth signing."