Originally set for release in March 2010. The studio pushed back release when test screenings reportedly did not impress Lionsgate executives. Reshoots were held in September 2010 in Shreveport, Louisiana.
Wormwood, the name of the forest where blood is shed, is also the name of a destructive entity in the Bible. This entity, a star whose name also translates as Bitterness, appears to cause widespread illness. According to Revelation 8:10-11, "The third angel sounded his trumpet, and a great star, blazing like a torch, fell from the sky on a third of the rivers and on the springs of water--the name of the star is Wormwood. A third of the waters turned bitter, and many people died from the waters that had become bitter."
Filming took place in Austria, Hungary and Croatia. Most of the principal photography took place in practical locations, with several days committed to filming on greenscreen. Principal photography was completed by April 2009, but the cast and crew re-gathered a few months later to film additional battle sequences, filming on greenscreen to save on travel. The reshoots were directed by Brett Ratner.
Originally development in 2000 when the spec script by screenwriter Bragi F. Schut and was purchased by MGM. The project moved from MGM to Columbia Pictures to Relativity Media, where the film was finally produced by Charles Roven and Alex Gartner.
Season of the Witch (2011) was produced by mega producer Charles Roven. A few of the films that Charles Roven has produced and has lined up to produce are: Three Kings (1999) Rollerball (2002) Scooby-Doo (2002) Bulletproof Monk (2003) Scooby-Doo 2: Monsters Unleashed (2004) Batman Begins (2005) The Brothers Grimm (2005) Get Smart (2008) Get Smart's Bruce and Lloyd: Out of Control (2008) The Dark Knight (2008) The International (2009) Season of the Witch (2011) The Dark Knight Rises (2012) Man of Steel (2013) American Hustle (2013) Warcraft (2016) Batman v Superman: Dawn of Justice (2016) Suicide Squad (2016) Wonder Woman (2017)