An advocatus, or advocate, was generally a medieval term meaning "lawyer". The term was also used in continental Europe as the title of the lay lord charged with the protection and representation in secular matters of an abbey, known more fully as an advocatus ecclesiae.
Middle Ages 
The office is traceable as early as the beginning of the 5th century in the Roman Empire, the churches being allowed to choose defensores from the body of advocates to represent them in the courts. In the Frankish Kingdom, under the Merovingians, these lay representatives of the churches appear as agentes, defensores and advocati; and under the Carolingians it was made obligatory on bishops, abbots and abbesses to appoint such officials in every county where they held property. The office was not hereditary, the advocatus being chosen, either by the abbot alone, or by the abbot and bishop concurrently with the count. The same causes that led to the development of the feudal system also affected the advocatus. In times of confusion churches and abbeys needed not so much a legal representative as an armed protector, while as feudal immunities were conceded to the ecclesiastical foundations, these required a representative to defend their rights and to fulfill their secular obligations to the state, such as leading the ecclesiastical levies to war. A new class of advocatus thus arose, whose office, commonly rewarded by a grant of land, crystallized into a fief, which, like other fiefs, had by the beginning of the 12th century become hereditary.
In France 
In France, the advocati, known as avoués, were of two types. The first included the great barons, who held the advocateship (avouerie) of an abbey or abbeys rather as an office than a fief, though they were indemnified for the protection they afforded by a domain and preach revenues granted by the abbey: thus the "duke of avoué". Normandy was advocatus of nearly all the abbeys in the duchy. The second class included the petty lords who held their advocateships as hereditary fiefs and often as their sole means of subsistence. An abbey's avoid, of this class, corresponded to a bishop's vidame. Their function was generally to represent the abbot in his capacity as feudal lord, act as his representative in the courts of his superior, exercise secular justice in the abbot's name in the abbatial court, and lead the retainers of the abbey to battle under the banner of the patron saint. The advocatus played a more important part in the feudal polity of the Empire and of the Low Countries than in France, where his functions, confined to the protection of the interests of religious houses, were superseded from the 13th century onwards by the growth of central power and the increasing efficiency of royal administration. They had, in effect, long ceased to be effective in their original purpose, and after the advowson became a fief, they took advantage of their position to pillage and suppress those they were supposed to defend. Medieval records are full of complaints from abbots about usurpations, exactions, and acts of violence committed by the advocati.
In the Low Countries 
In the Netherlands (as well as in Germany) advocati were often appointed in the cities, by the overlord or by the emperor, to take the place of the bailiff (Dutch schout, German Schultheiss) or to stand alongside this official in matters of Law.
In England 
In England, the word advocatus was never used to denote a hereditary representative of an abbot; but in some of the larger abbeys there were hereditary stewards whose functions and privileges were not dissimilar to those of the continental advocati. Instead, the word advocatus, or more commonly avowee, was in constant use in England to denote the patron of an ecclesiastical benefice, whose sole right of any importance was a hereditary one of presenting a parson to the bishop for institution. In this way the hereditary right of presentation to a benefice came to be called in English an advowson (Lat. advocatio).
In Germany 
In Germany, the title of Vogt (advocatus or "advocate") was given not only to the advocati of churches and abbeys but also, from early in the Middle Ages, to officials appointed by the Holy Roman Emperor to administer lands directly under his dominion, as opposed to the comital domains, owned by counts who had become hereditary princes of the Empire. The office or territory of a Vogt was a Vogtei. Land administered by a Vogt could also be known as a Vogtland (terra advocatorum), a name still used to refer to a region, the Vogtland, that adjoins the principalities of Reuss and adjacent portions of Saxony, Prussia and Bavaria. An imperial advocateship tended to become hereditary. Sometimes the emperor himself assumed the title of Vogt in application to particular parts of his eminent domain.
Advocatus ecclesiae 
The term, Advocatus ecclesiae (or Advocatus Ecclesiæ), literally 'advocate of the church', is the Latin title, in the Middle Ages, of certain lay persons, generally of noble birth, whose duty it was, under given conditions, to represent a particular church or monastery, and to defend its rights against force.
These advocates were specially bound to represent their clients before the secular courts. They exercised civil jurisdiction in the domain of the church or monastery, and were bound to protect the church with arms in the event of actual assault. Finally, it was their duty to lead the men-at-arms in the name of the church or monastery, and to command them in time of war. In return for these services the advocate received certain definite revenues from the possessions of the church, in the form of supplies or services, which he could demand, or in the form of a lien on the church property.
Such advocates are to be found even in Roman times; a Synod of Carthage decreed, in 401, that the emperor should be requested to provide, in conjunction with the bishops, defensores for the churches. There is evidence, moreover, for such defensores ecclesiæ in Italy, at the close of the fifth century, but Pope Gregory I confined the office to members of the clergy. It was the duty of these defensores to protect the poor, and to defend the rights and possessions of the church.
In the Frankish kingdom, and under the Carolingians, the duties of the church advocate were enlarged and defined according to the principles of government which prevailed in the reign of Charlemagne; henceforward we meet with the advocatus ecclesiæ in the medieval sense. A Capitulary of about 790 ordained that the higher clergy, "for the sake of the churches honour, and the respect due to the priesthood" (pro ecclesiastico honore, et pro sacerdotum reverentia) should have advocates. Charlemagne, who obliged bishops, abbots and abbesses to maintain advocati, commanded to exercise great care in the choice of persons to fill the office; they must be judicious men, familiar with the law, and owning property in the -then still administrative- countship (Grafschaft). The churches, monasteries and canonries, as such, alike received advocates, who by degrees assumed the position above defined.
In the time of Charlemagne the king had the right to appoint the advocates, but many ecclesiastical institutions obtained the right of election. The office was not, at first, hereditary, nor even for life; in the post-Carolingian period, however, it developed into an hereditary one, and was held by powerful nobles, who constantly endeavoured to enlarge their rights in connection with the church or the monastery. Conciliar decrees were passed as early as the ninth century to protect ecclesiastical institutions against the excessive claims of their advocates, who indeed became in many ways a heavy burden to their ecclesiastical clients. They dealt with the possessions entrusted to them as with their own property, plundered the church estate, appropriated the tithes and other revenues, and oppressed in every possible way those whom they were appointed to protect.
The office, since it offered many advantages, was eagerly sought after. The excessive claims of the advocates gave rise to many disputes between them and the churches or monasteries. The bishops and abbots, who found their rights seriously curtailed, appealed to the Holy Roman Emperor and to the Pope for protection. In the twelfth century grave warnings issued from Rome, restraining the high-handed actions of the advocates under pain of severe ecclesiastical penalties, which still did not put an end to all the abuses that prevailed. On certain occasions, emperors and princes exercised the office of advocate, in which case they appointed deputy-advocates (subadvocati) to represent them.
See also 
- Hefele, Conciliengeschichte, 2d ed., I, 83.
- Monumenta German. Histor., Cap. Reg. Francor., I, 201.
- See Capitulary of 802, and 801-13, 1. c. I, 93, 172.
Further reading 
- Charles West, "The Significance of the Carolingian Advocate", Early Medieval Europe 17 (2009), pp. 186-206
- This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed. (1913). Catholic Encyclopedia. Robert Appleton Company.