"the public dances of women, which may do so much harm and mischief"

1.
An excerpt from A History of Byzantium by Timothy E. Gregory, 2 ed., 2010, Wiley:

It is clear that some practices derived from paganism continued to survive into the Byzantine period. Some of these apparently were connected with ancient festivals of the gods Pan (the so-called Bota) and Dionysos (the Brumalia). These festivals were no longer closely associated with religion, but rather were opportunities for dancing, drinking, and general carousing - much, perhaps, like the modern Mardi Gras. The bishops assembled for the Council in Trullo were shocked by such behavior and one of the Canons (decrees) condemned the festivals, but also provides us with important evidence of the kind of behavior that was apparently still going on, well into the Byzantine Empire:

CANON LXII
"The so-called Calends, and what are called Bota and Brumalia, and the full assembly which takes place on the first of March, we wish to be abolished from the life of the faithful. And also the public dances of women, which may do so much harm and mischief. Moreover we drive away from the life of Christians the dances given in the names of those falsely called gods by the Greeks whether of men or women, and which are preformed after an ancient and un-Christian fashion; decreeing that no man from this time forth shall be dressed as a woman, nor any woman in the garb suitable to men. Nor shall he assume comic, satyric, or tragic masks; nor may men invoke the name of the execrable Bacchus when they squeeze out the wine in the presses; nor when pouring out wine into jars [to cause a laugh], practicing in ignorance and vanity the things which proceed from the deceit of insanity. Therefore those who in the future attempt any of these things which are written, having obtained knowledge of them, if they be clerics we order them to be deposed, and if laymen to be cut off."
[p. 174]

2.
Here are two excerpts from The Council of Trullo (691-692): A Study Relating to Paganism, Heresy, and the Invasions by Frank R. Trombley, published in Comitatus: A Journal of Medieval and Renaissance Studies, 1978. The full article is viewable at eScholarship.Org here. Following those two excerpts there is also an overview of some other "Pagan practices" prohibited by the Trullo Canons that Trombley (who is also the author of the magnificent two volume Hellenic Religion and Christianization) discusses in his article:

a.
The survival of pagan cult practices among Christians alarmed imperial and ecclesiastical authorities, it seems, partly because the empire still had a highly visible, but not very large pagan population. Apostasy was an ever present danger. Very little information survives in the sources about the continuation of pagan cults in Anatolia and Greece after the mid-sixth century. It will be recalled that in 542 John of Ephesus [c.507 - c.586], with the assistance of Deuterius, the metropolitan of Caria, undertook the catechization of the pagans of western Anatolia (the regions of Asia, Caria, Lydia, and Phrygia). John himself penetrated the mountainous country near Tralles, and convinced many idol-worshipers to embrace Christianity. He directed these activities from a monastery at D'RYR', and at one time entered the rough mountain area where a celebrated pagan temple, containing fifteen hundred idols, existed. The conversion of these populous regions was accomplished by the foundation of more than one hundred churches and monasteries. The maintenance of these institutions was necessary to prevent the apostasy of the vast new congregation. The population of the regions evangelized by John practiced the enthusiastic cult of Cybele .... The strength of paganism in these areas, even after John's missionary work, is attested by the persistence of [the cult of Cybele] in Caria well into the eighth century ....

Pagan groups persisted in Greece as well, although the exact character of their cult is not attested. Constantine VII Porphyrogenitus reports in De Administrando Imperio that the city of Maina in the Peloponnese was inhabited by a non-Slavic population. The people referred to themselves as 'Hellenes' and gave out that in ancient times they had been idolators in the fashion of the Greeks of old. They accepted conversion during the reign of Basil I (867-886). [For more on the Hellenes of Maina, see the excerpt from J.B. Bury in section 3 of this post, below.]
[pp. 4-5]

b.
The Sixty-first Canon describes a different type of paganism, one not unique to Graeco-Roman culture, yet referred to with the term hellenika. In times of cataclysm, such as the invasions of the seventh century, fortune tellers and seers do a windfall business. The Canon catalogues several types of diviners and charlatans. Diviners (mantai) of the usual sort, who read palms and dishes, are recorded, including the so-called hecatantarchoi, old men who claimed to be divine, and convinced the simple folk of this by displaying bears and other other animals, and then making them do tricks. Soothsayers went about making pronouncements regarding fate (tyche), destiny (heimarmene), and genealogy (genealogia) (the prediction of the future by analysis of the circumstances of birth, including the position of the heavenly bodies), which this Canon refers to as the 'nonsense of error.' Several other types of diviners foretold events after gazing at the shapes of clouds at sunset, and 'magicians' (geteutai), who invited themselves into the houses of Christian women by singing psalms, muttering the names of the theotokos and martyrs, and wearing amulets and charms. It is recorded that the purveyors of amulets (phylakterioi) were doing a good business.

The Sixtieth Canon reflects another aspect of the pagan subculture. Certain persons, it is reported, imitated the manners of the possessed. Like the soothsayers and diviners, they probably did this for private gain. Women practiced this, if Balsamon's conjecture is correct, in oracular fashion resembling that of the priestesses of Delphi. Since the pagan deities were regarded as demons, persons who feigned possession had, by the injunction of this Canon, to undergo the same discipline of exorcism as those actually possessed.
[p. 6]

c.
Other Pagan practices specifically forbidden by the Canons enacted at the Council of Trullo (in addition to those named above) included (as described by Trombley):

• Gaming with dice. (50th Canon)
• Mime shows. (51st Canon)
• Commemorating the new moon (numeniai) by "erecting a pyre in front of one's home or workshop and leaping over it." (65th Canon)
• Law students were forbidden to practice various Pagan customs (hellinika ethe), and this specifically included attending the theater or horse races, or wearing "unusual or bizarre clothing". (71st Canon)
• According to the 71st Canon, law students were also forbidden to study "the sciences" (ta mathemata).
• Men were forbidden to visit bath houses with women. (77th Canon)
• Curses and oaths in the names of Pagan Gods (horkoi hellnikoi). (94th Canon)
• The wearing of seductive hair styles. (96th Canon)
• "Paintings that bewitch the sense of sight, whether communicated on tablets or in any other way, which are destructive to reason, and move it toward the fueling of shameful passions." (100th Canon)

3.
An excerpt from History of the Eastern Empire from the Fall of Irene to the Accession of Basil: A.D. 802-867 by J.B. Bury, first published in 1912:

It is interesting to note that on the promontory of Taenaron in Laconia a small Hellenic community survived, little touched by the political and social changes which had transformed the Hellenistic into the Byzantine world. Surrounded by Slavs, these Hellenes lived in the fortress of Maina, and in the days of Theophilus [Emperor from 829-842] and his son [Michael III, ruled from 842-867] still worshipped the old gods of Greece. But the days of this pagan community were numbered; the Olympians were soon to be driven from their last recess. Before the end of the century the Mainotes were baptized [under Basil I].
[p. 381 in the 2008 Cosimo Classics edition]

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