^^ The church during the Ottoman Empire must have been more ferocious than most fascist regimes in the 20th century. I am afraid this is a claim with no substance.
BTW read your source more carefully.
This isn't so. Arvanites and others were under the Rum milet and tight up with the Byzantine Church they had no ''nationality'' besides being an Orthodox Christian.
The present state of the Morea called Peloponesus, Bernard Randolph, an English traveler, London, 1686:
"The Albanians from Arcadia are three times more numerous than the Turks."
Who are these Albanians? Why did Bernard Randolph not find or report on any Hellenes in Arcadia as a whole, in 1686? We do know that modern Neo-Hellenes appear on the maps in the 19th century, but who are these modern Hellenes? Did Randolph's 'Arcadian Albanians' of the late 17th century evaporate within a hundred years or so, to be replaced by a new population of modern Hellenes? We do not find any historical reports from 1686 until the 19th century of large-scale population movements into Arcadia, and/or extermination or genocide of the 'Arcadian Albanians'. It seems evident and likely, that the logical explanation is that the native inhabitants of Arcadia (both Arvanites and Vlachs) exchanged their native tongue for modern Greek.
The 10th century "Byzantine" anonymous epitomizer of Strabo wrote:
«Καὶ νῦν δὲ πᾶσαν Ἤπειρον καὶ Ἑλλάδα σχεδὸν καὶ Πελοπόννησον καὶ Μακεδονίαν Σκύθαι Σκλάβοι νέμονται»
"And now most of Epirus and Hellas and Peloponnesus and Macedonia are inhabited by 'Scythi-Slavs'."
Vgl. Müller, Geographi Graeci Minores II S. 574.
And for Western Peloponnese in particular:
«Νῦν δὲ οὐδὲ ὄνομά ἐστι Πισατῶν καὶ Καυκώνων καὶ Πυλίων· ἅπαντα γὰρ ταῦτα Σκύθαι νέμονται»
s. Müller, Geogr. Graeci Minores II S. 583.
"And now not even the names of the Pisatans, the Caucones or the Pylians survive. All these regions are inhabited by 'Scythians'."
Who were these Scythians and/or Scythi-Slavs? What happened to them? Did they evaporate into thin air at some later stage of history? Were they exterminated fully? One thing seems evident - whoever these 'Scythians' were, they settled into Peloponnese lands and regions that were (already) largely empty. (If not, these 'Scythians' exterminated or drove out whatever locals they found.)
«Tαῦτα [τὰ Σκλαβικά ἔθνη] δὲ ὁ ἡμέτερος ἐν θείᾳ τῇ λήξει γενόμενος πατὴρ καὶ Ῥωμαίων αὐτοκράτωρ Βασίλειος τῶν ἀρχαίων ἐθῶν ἔπεισε μεταστῆναι καὶ, γρακῶσας, καὶ ἄρχουσι κατὰ τὸν Ῥωμαϊκό τύπον ὑποτάξας, καὶ βαπτίσματι τιμήσας, τῆς τε δουλείας ἡλευθέρωσε τῶν ἑαυτῶν ἀρχόντων, καὶ στρατεύεσθαι κατὰ τῶν Ῥωμαίοις πολεμούντων ἐθνῶν ἐξεπαίδευσεν, οὕτω πως ἑπιμελῶς περὶ τὰ τοιαύτα διακείμενος, διό καὶ ἀμερίμνους Ῥωμαίους ἐκ τῆς πολλάκις ἀπὸ Σκλάβων γενομένης ἀνταρσίας ἐποίησεν, πολλὰς ὑπ΄ἐκείνων ὀχλήσεις καὶ πολέμους τοῖς πάλαι χρόνοις ὑπομείναντας».
English Translation by George T. Dennis's "Tactica" (page 471):
"Our father, Emperor of the Romans, Basil, now in the divine dwelling, persuaded these peoples [the Slavic tribes] to abandon their ancient ways and, having tought them the greek language,, subjected them to rulers (archontes) according to the Roman model, and having graced them with baptism, he liberated them from slavery to their own rulers and trained them to take part in warfare against those nations warring against the Romans. By these means he very carefully arranged matters for those peoples. As a result, he enabled the Romans to feel relaxed after the frequent uprisings by the Slavs in the past and the many disturbances and wars they had suffered from them in ancient times".