Was every monk, priest, nun, etc. always able to read and write? Or was it only a requirement for some of the clergy?
Thank you!
The answer primarily depends on the period, region, rank and gender (not necessarily all were literate), but I hope my previous post in: How knowledgeable and respected was the average village priest during the 1300s? might be helpful for the general circumstances in medieval Europe after Council of Lateran IV in 1215.
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As for Early Middle Ages (especially after the Carolingian Renaissance in the late 8th century), cathedral and monastic schools occupied the the main educational institution in the society (some children of the aristocrat might who was not to be monks/ nuns also attended the school temporary, as I alluded to before in: In the TV period drama "Arn", 12th century Swedish Arn and his sweetheart Cecilia Algotsdotter move in and out of cloistered life. Is that supported by historical evidence?), but the entrance to the monastery was primarily meant to open for those who were born in the nobility (see also my previous post in: Was it common for premodern Catholic monks and nuns to join monasteries/nunneries without religious callings because they didn't want to starve?...... ).
On the other hand, roughly before the 12th century, local priests, especially those who served in the proprietary church founded on the private land of the lay nobles, were often drawn from lower social milieu (including "unfree" in legal status). Carolingian capitularia and later synodal statutes (decree of the provincial church council) sometimes mentions how the aspirant local priests to be educated, but it would be not always so easy to observe the standard as good as post-Lateran later Middle Ages (see the first linked post), I suppose.
Hamilton quotes the following decree/canon 38 of Council of Hohenaltheim (916) on the obligation of ex-serf priest to his lord:
"If anyone for love of God chooses one of his serfs, teaches him letters (docuerit litteras), grants him liberty, makes him a priest (by request to the bishop) and....gives him food and cloths, but afterwards, flown with pride, he refuses to celebrate mass and the canonical hours and to sing psalms for his lords and will not obey them properly, saying that he is a freemen and can become the man of anyone he choose [he should be excommunicated, and if obdurate, degraded from the priesthood and lose his free status (Hamilton 2013: 96, original text in Latin is to be found in MGH Conc. VI-1: 39)."
In some cases in post-Carolingian to (early) 12th century, even a few church dignitaries (especially those who had lay background and ordained in adulthood) apparently had difficulty in reading and writing (in Latin). The following passages is a famous anecdote on Bishop Svend "the Norwegian" of Roskilde (d. 1088) who would then studied hard to redeem himself in later tradition (Saxo Grammaticus), but I myself am not so sure about the historicity of this anecdote itself (that is to say, the anecdote does not directly refer to historical Svend's literacy, rather a cliche):
"He [the king of the Danes] appointed Svend, the man from the region of Norway and in his retinue, [to the bishop]. He [Svend] was with full of virtues and good at calculation, but knew little about the complexity of letters. This Svend was translated from the secular officer to the sacerdotal one, and even though he had a problem in the lack of Latin competence, he was excelled at preaching in the vulgar language. Other people who saw Svend was preferred by the king due to his excelled talents and virtues, worked a scheme out of scorning him with the contempt on his inexperience. To achieve the scheme, they thus deleted a letter of the word in the liturgical book. So, when he made the prayer to the king in solemn manner and referred to the king as godly servant (famulus), Svend disgraced himself by reading "a mule (aemulus)" due to the altered page, since he couldn't correct the mistake in spelling. Thus, thanks for this circumstances that made a laugh at the inexperience of the lector, those who attended laughed their head off by this vulgar joke without limit......(Saxo, Gesta Danorum, XI-7-7)
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