The 41-year-old former Barca boss left Camp Nou in 2012 having won 14 trophies with the Liga side during his four seasons in charge and has signed a deal with the Bundesliga club until 2016.
Guardiola had been linked with a host of top-flight clubs across Europe, but Bayern CEO Karl-Heinz Rummenigge said in a statement he was delighted to have captured the Spaniard.
"We are very pleased that we have succeeded [in appointing] the football expert Pep Guardiola, who was courted by many famous clubs and contacts," said CEO Karl-Heinz Rummenigge.
"Guardiola is one of the most successful coaches in the world and we are sure that he can [help] not just Bayern, but German football, shine."
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