Serbian medieval literature is very rich with around 500 separate genres. Medieval works are mostly a mix of history, legal theory, theology, writing, and philology. While there were several works of poetry written in the Serbian literature in the Middle Ages, there are only few dramas; published novels were mostly adaptations and translations. The earliest writings in Serbian were religious works. Religions were historically the first institutions that persisted despite political and military upheavals. They were the first organizations to see the value in recording in writing their history and policies. Serbia's early religious documents date back to the 10th and 11th centuries. In the 12th century, Saint Sava developed the art form of religious writing. He worked to bring about an artistic aspect to these writings, also based on earlier works.