The abolition of the poll tax in Illyricum and Thrace made automatically the estate owner’s guarantee for this void and with that the census registration and the colonate. To prevent loss of labour in these war-stricken provinces the emperors introduced in 371 and 398 the rule that, although now free from subjection, former coloni had to remain on the estate and render services. This ‘free’ colonate, which must have existed before, was also introduced in Palestine in 386. The status of the ‘free’ coloni in Byzantium looks very similar to the status of the serfs, villeins, or Hörigen in medieval West-Europe, who also were tied to a plot of land. But there were differences too: unlike in some cases there, these coloni were not in any way subjected to the jurisdiction of their masters, nor required to ask permission for marriage, etc. Further, as far as we know, there is no link between the two phenomena. If we would call them nevertheless serfs, it should always be with the adjective Byzantine.

In the fourth and fifth centuries, the emperors had to combat the patrocinium: the protection offered by powerful persons to towns and individuals. This protection was often used for evading public law duties. The title in the Code deals only with Egypt, where it seems to have been rampant or been most detrimental, notwithstanding that it is also attested for Syria. It must have existed in other provinces as well. Yet, it does not seem in the west to have required legislation. Also coloni took advantage of it, offering patrons entire hamlets. As a result they seem to have neglected to work for their estate owners. In this context the coloni homologi turn up. Connecting this with CTh 13.10.7, it concerns most probably coloni registered on one tax list. They had to provide the aggregate of the poll tax, regardless of the number of present coloni. The solution was to combine lists and correct by cross-linking fiscal accounts.