Probably this fact, together with the more general fact of the absorption in most things of the German in the Roman, accounts for the substitution of the patrocinium for the comitatus which took place under the Merovingians.
He forced them to become his dependants in return under a great variety of forms, but especially developing thereby the precarium land tenure and the patrocinium personal service, and organizing a private jurisdiction over his tenants, and a private army for defence.
The patrocinium they were made ready to understand by the existence of a somewhat similar institution among themselves, the comitatus, described by Tacitus.
So long as they were fulfilled, he, and his heir after him, held the fief as his property, practically and in relation to all under tenants as if precarium and patrocinium were lacking.
As used for protection in later Roman days the precarium gave rise to what was called the commendation of lands, patrocinium fundorum.
The same class continued to furnish the king's men, and to form his household and body-guard whether the relation was that of the patrocinium or the comitatus, and to be made noble by entering into it.
The special features of the institution were the strong tie of faith and service which bound the man, the support and rewards given by the lord, and the pride of both in the relationship. The patrocinium might well seem to the German only a form of the comitatus, but it was a form which presented certain advantages in his actual situation.
Grants of land of the Merovingian kings had carried with them ownership and not a limited right, and the king's patrocinium had not widened in extent in the direction of the later vassal relation.