The Entourage actor was first linked to the biopic earlier this month.
Piven will play Harry Gordon Selfridge, the American entrepreneur who founded the British department store Selfridges.
Katherine Kelly (Coronation Street) will star as Lady Mae, an alluring socialite who helps Harry as he builds his empire.
Also cast in the project are Grégory Fitoussi (Spiral), Aisling Loftus (The Borrowers), Zoe Tapper (Survivors), Frances O'Connor (A.I. Artificial Intelligence) and Trystan Gravelle (Anonymous).
"It's impossible to read about the real Harry Selfridge and not be enthralled," said ITV's Kate Lewis. "Here's a man that had it all and lost it all in the most spectacular fashion. His life and the extraordinary legacy he left behind are dripping with drama."
The 1909-set series will run for ten 60-minute episodes. Andrew Davies (Bleak House) is the lead writer, alongside Kate Brooke (Case Sensitive) and Kate O'Riordan (The Bad Mother's Handbook).
Mr Selfridge will go into production in April in London, for transmission on ITV1 during 2013.
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