Hildegard von Bingen, one of the most important women of the medieval age, will be the subject of veteran German filmmaker Margarethe von Trotta's next feature film. The project will go into production at locations in Hessen and Bavaria from late summer after many years of research and preparation.

Hildegard von Bingen (1098-1179) was a visionary, poet, composer, naturalist healer and theologian, who founded convents, corresponded with secular and ecclesiastical leaders and, remarkable for a woman of her time, produced an impressive body of written work.

This new project marks the second collaboration between von Trotta and Clasart Filmproduktion after I Am The Other One (Ich Bin Die Andere), starring Katja Riemann, August Diehl and Armin Mueller-Stahl, and the third with Clasart's Markus Zimmer who co-produced her 2003 film Rosenstrasse through the parent company Tele Muenchen. As with the previous films, the German theatrical release will be handled by Concorde Filmverleih.

News of von Trotta's next feature was unveiled as her former husband Volker Schloendorff is now on the final straight of preparations for his long-gestating adaptation of the Donna Cross novel Pope Joan which will go into production in Bulgaria in mid-May.

Cross's bestseller tells the story of Johanna von Ingelheim (to be played by Franka Potente), who succeeded in entering the highest ranks of the Roman clergy disguised as a man and was elected Pope in 853 - a story that the Vatican claims is merely legend. The book spent months in the bestseller lists in Germany when it was published in 1996 and has since sold 4m copies.

The international, English-language project will be produced by Constantin Film in co-production with Ufa Film & TV Produktion, Italy's Medusa and Spain's Filmax at studios in Sofia and on location in the city's Alexander Nevsky Cathedral as well as in the towns of Widin and Belogradtschik. Plamen and Vladimir Voynovsky's Sofia-based Film House Bright Ideas Ltd. have been recruited as the Bulgarian service company.

Following a strategy adopted for the production of another successful Constantin title, Oliver Hirschbiegel's Downfall, the producers will make a two-part TV version of Pope Joan in addition to the theatrical film.