Villa boss Steve Bruve has raided his former club to sign the 29-year-old, who he managed at Sunderland and Hull.
Elmohamady, who’s signed a three-year deal at Villa Park, will now link up with the squad in Germany.
“Aston Villa is a great club and I am thrilled to join – it’s one of the very biggest clubs in England and its history and tradition is there for all to see,” said the Egyptian.
“It’s a great time to join too as we look for promotion to the Premier League.
“I will give absolutely everything to help us achieve that goal.”
Elmohamady is Villa’s third signing of the summer following the captures of John Terry and Sam Johnstone.
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