The project will chart the early romance and subsequent marriage of Ernest Hemingway (Clive Owen) and Martha Gelhorn (Nicole Kidman).
Actors now confirmed for the film include Temple Grandin star David Strathairn as Hemingway's friend John Dos Passos, 300's Rodrigo Santoro as Spanish loyalist Zarra, Heroes actor Santiago Cabrera as war photographer Robert Capa, and Molly Parker and Parker Posey as Hemingway's second and fourth wives respectively.
Saverio Guerra, Peter Coyote, Diane Baker and Monk's Tony Shalhoub have also signed up for roles, while Metallica drummer Lars Ulrich will appear as Dutch documentarian Joris Ivens.
Quills director Phillip Kaufman will direct the project, which is being executive produced by The Sopranos star James Gandolfini.
Hemingway & Gellhorn will air on HBO in 2012.