What is a series of mutual obligations where lords and vassals depended on one another for support

The byzantine empire drew on the long blank tradition of the roman empire. this included the laws and edicts of former roman emperors as well as laws from the roman republic, such as the blank one byzantine blank wanted to simplify the laws so he appointed committees to go through the roman laws and decisions. they produced a unified system of laws known as blank either -emporer -legal -justinians code -patriarch -pax romania -religious -the apian way -twelve tables hurry im timed on a quiz