Following the arrivals of Artur Boruc and Adam Federici, the Cherries have completed a deal for King, with the Norway international putting pen to paper on a three-year contract.
The 23-year-old was offered new terms to stay at Ewood Park, but has opted to join Eddie Howe’s squad ahead of the club’s first season in the Barclays Premier League.
King made 23 appearances in all competitions during the 2014/15 campaign, starting against his new team-mates in a 3-2 away defeat for the Cherries in August.
The former Manchester United player, who has also represented Hull City and Preston North End on loan, made headlines in this season’s FA Cup fifth round.
Having featured in the victory over Swansea City in the previous stage, he scored a hat-trick in a 4-1 win against Stoke City to continue Rovers’ impressive run in the competition.
Since making his international debut, King has been part of Norway’s qualification campaigns for the 2014 World Cup and 2016 European Championships, with one of his most recent caps coming in a friendly at Wembley against England back in November.
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