9th century in law

posthumous ecclesiastical trial of Pope Formosus

alt=|thumb|250x250px|Leo VI (right) and Basil I (left), from the 12th-century Madrid Skylitzes. The Basilika (, "the imperial [laws]") was a collection of laws completed in Constantinople by order of the Byzantine emperor Leo VI the Wise during the Macedonian dynasty. This was a continuation of the efforts of his father, Basil I, to simplify and adapt the Emperor Justinian I's Corpus Juris Civilis code of law issued between 529 and 534 which had become outdated. The term comes from the Greek adjective Basilika meaning "Imperial (laws or enactments)" and not from the Emperor Basil's name; both

The Epanagoge (, "return to the point"), more properly the Eisagoge (, "Introduction [to the law]"), is a Byzantine law book promulgated in 886. Begun under Basil I the Macedonian (r. 867–886), it was only completed under his son and successor, Leo VI the Wise (r. 886–912). As its name suggests, it was meant to be an introduction to the legislation of the Basilika, published later during Leo's reign.

capitulary

contract between King Lothair I of Italy and Pope Eugene II