The play, which is directed by Roxana Silbert using a new translation by Mark Ravenhill, charts the 17th century scientist’s extraordinary fight with the church over his assertion that the earth orbits the sun.
A Life of Galileo runs in the RSC’s Swan Theatre from 31 January to 30 March 2013 and will run in repertoire with The Orphan of Xhao and Boris Godunov as part of the A World Elsewhere trilogy.
McDiarmid, who plays the title role, will be joined in the principal cast by Jodie McNee, who returns to the company to play Virginia after roles last season including Isabella in Silbert’s Measure for Measure, and Written on the Heart (which transferred to the West End).
They will join the acting ensemble currently in rehearsal for artistic director-elect Gregory Doran’s The Orphan of Xhao by James Fenton and outgoing AD Michael Boyd’s production of Boris Gudonov. Further casting details will be announced in due course.
Ian McDiarmid previously worked for the RSC in the 1976-7 season and then later in the 1984-5 season, in plays which include: Schweyk in the Second World War, The Maple Tree Game, Henry V, Dingo, Destiny, Macbeth and Much Ado about Nothing.
Other recent theatre includes: Timon in Timon of Athens for Chicago Shakespeare Theatre, Maximus in Emperor and Galilean for the National Theatre, The Elector in The Prince of Homburg, the title role in John Gabriel Borkman for the Donmar Warehouse and Six Characters in Seach of an Author for Headlong.
Roxana Silbert said: "Ian is a brave, fearless, charismatic actor brimming with the acute intelligence demanded by the role of Galileo".