Gratian's Decretum

Timeline

1. c. 1139–1140Bologna · Emilia-RomagnaGratian (also Gratianus) compiled the canons of successive ages into a teachable Decretum at Bologna, organizing material on marriage, holy orders, jurisdiction, and church property through case-style questions, with brief glosses reconciling conflicts. The text of c. 1140 became the basic textbook for canon law courses.
2. 1140–1159Schools of Bologna and Paris · FranceManuscripts of the Decretum were taught at Bologna, Paris, and elsewhere, with glossators (decretists) resolving difficulties article by article. Papal courts and local episcopal tribunals began citing its structure in handling marriage and holy orders cases, giving canon law a disciplinary status parallel to Roman law.
3. 1234–1917Roman Curia · LazioOfficial compilations of the 13th century, such as Gregory IX's Decretals, together with Gratian's text, formed the Corpus Juris Canonici. After the 1917 Code of Canon Law was promulgated, the medieval decretal system ceased to be current law, but the Decretum remains a core document in the history of Western jurisprudence.