Michael, 23, caught the eye last season with some impressive performances for the Shoguns, making 16 appearances for the West Country side.
The English-born youngster was brought up in Australia and featured as a New South Wales Waratahs squad member last season before opting to a move to England and the Zurich Premiership. The switch of allegiance paid off for Michael, who was rewarded for his strong performances with the Shoguns with a call-up to Clive Woodward's England squad for the non-cap international against the Barbarians last month.
Jack Rowell said that Michael will be an important addition to the Bath Rugby squad next season, and believes that the continued rehabilitation of Adam Vander will provide Michael with an opportunity to prove himself.
"Michael is an extremely promising young player whose performances for Bristol at the end of last season were rewarded with an England call-up against the Barbarians" said Rowell. "Adam Vander, who had an outstanding season for us, is currently sidelined with a serious foot injury and the latest prognosis is that he will not be available for us until late autumn if his rehabilitation goes well. Therefore Michael along with promising England under 21 international James Scaysbrook will be vying for a place in a strengthened back row next season."
Michael said that he was looking forward to challenging for a place in the Bath Rugby side next season.
"I am excited about the prospect of joining one of the most prestigious clubs in England and can't wait to play at the Rec. I am also looking forward to playing with a number of the internationals in the Bath Rugby pack and am excited about the challenge ahead."
Michael is summer signing number eight for Bath Rugby following props Duncan Bell and David Flatman, scrum half Martyn Wood, centre Andrew Higgins, lock Rob Fidler, hooker Christian Balshen and back row player Jonathan Pettemerides to the Recreation Ground. The back row star will meet up with his new team mates when pre-season training gets under way in two weeks time.