A 1977 graduate of Framingham South, the Cavaliers signed him to a three-year deal that includes a team option for a fourth year and could be worth $20 million, reported the Boston Herald.
"I feel strongly about my fit for the job and this team's potential," Blatt said in a news release. "This is an opportune time to join the Cleveland Cavaliers. We are going to work extremely hard to achieve the kind of results we all expect and know are possible."
USA Today reported the deal "is a bold and laudable hire by the Cavs. Blatt has no NBA experience as a player or coach. But he is a well-respected and accomplished international coach."
After graduating from Framingham South High School, Blatt, a point guard, played hoop at Princeton University.
In 2012, Blatt, 55, coached the Russian national team to the bronze medal at the Summer Olympics in London.
Blatt has spent 20 years abroad coaching in Israel, Russia, Turkey and Greece.
He also will become the first European head coach to be picked to run an NBA team, reported the Cleveland Plain Dealer.
Blatt will be introduced by the team Wednesday, one day before the club picks first in this year's NBA draft.
The Cavs finished 33-49 and missed the playoffs for the fourth straight season, according to the NBA.
"David is a great basketball coach and a special person,'' Cavs General Manager David Griffin said in a press release. "His abilities to communicate, to build relationships with his players and to foster winning environments at several stops throughout Europe and across the highest levels of International competition speaks for itself. He brings unbridled passion, energy and creativity to his craft. These qualities have enabled David to reach a level of success that is truly unique.
"I have watched David's work for many years. He has an uncanny ability to adapt his system to maximize the talents of his teams year after year. That is why I am very confident he will make a smooth transition to the NBA," added Griffin.
Former Cav Anthony Parker, now a NBA scout in Orlando, played for Blatt in Israel and often cited him as his favorite coach, calling him one of the top basketball coaches in the world, reported the Cleveland Plain Dealer.