Niketas Choniates describes the contempt and the mockery of the villagers around Constantinople at the refugees from the city:

Οἱ δ’ ἀγκροῖκοι καὶ ἀγελαῖοι ἐπεκερτόμουν μᾶλλον τοῖς ἐκ Βυζαντίου ἡμῖν καὶ τὴν ἐν πτωχείᾳ καὶ γυμνότητι κακουχίαν ἰσοπολιτείαν ἀφρόνως ὠνόμαζον, οὐ τοῖς τῶν πέλας κακοῖς παιδευόμενοι. πολλοὶ δὲ καὶ ἀνομίαν ὑπολαμβάνοντες “εὐλογητὸς Κύριος, ὅτι πεπλουτήκαμεν” ἔλεγον, ὀλίγου τὰς τῶν συμφυλετῶν οὐσίας ἀποδιδομένας ὠνούμενοι. οὐ γάρ πω βουθοίνας εἰσῳκίσαντο Λατίνους, καὶ εἴδοσαν, ὅπως μὲν τὸν οἶνον ἄκρατον ὁμοῦ καὶ ζωρότερον ὥσπερ καὶ τὸν χόλον ἀκέραστον χέουσιν, ὅπως δὲ Ῥωμαίοις ἐν ὑπερηφανίᾳ καὶ ἐξουδενώσει προσφέρονται.

Van Dieten, J. (ed.), Nicetae Choniatae historia (CFHB 11, Berlin 1975), pp. 593-594.

Niketas Choniates's account of the plundering of monuments in Constantinople after the establishment of the Latin Empire:

Ἐκ πρώτης δ’ ὅ φασι γραμμῆς τὸ ἐθνικὸν παραδεικνύντες φιλόχρυσον ἐννοοῦσι πόρον λημματισμοῦ καινόν τε ἅμα καὶ λαθόντα ξύμπαντας, οἳ τὴν βασιλίδα πόλιν ἐσκύλευσαν. τὰς γὰρ τῶν βασιλέων θήκας ἀνοίξαντες, ὁπόσαι ἔνεισι τῷ ἡρῴῳ τῷ περὶ τὸ μέγα τέμενος ἱδρυμένῳ τῶν τοῦ Χριστοῦ μαθητῶν, λωποδυτοῦσι νυκτὸς ἁπάσας καὶ παναθεμίτως ἐγκολπίζονται, εἴ τις χρύσειος κόσμος ἢ μαργάρων σφαίρωμα ἢ λίθος διαυγὴς καὶ πολύτιμος ἀδιάφθορος εἰσέτι ταύταις ἐνέκειτο. εὑρόντες δὲ καὶ τὸν νεκρὸν Ἰουστινιανοῦ τοῦ βασιλέως τοῖς μακραίωσιν ἀπαραλύμαντον ἔτεσι τὸ μὲν ὁραθὲν ἐν θαύματι ἔθεντο, τῶν δὲ νεκροταφίων οὐμενοῦν οὐδ’ ὅλως ἀπέσχοντο. ἔστιν οὖν εἰπεῖν ὡς οὔτε τῶν ἔτι ζώντων, οὔτε μὴν τῶν ἀπελθόντων οἱ ἐκ γενῶν τῶν ἑσπερίων ἐφείσαντο, ἀλλ’ ἐκ θεοῦ καὶ τῶν αὐτοῦ θεραπόντων ἀρξάμενοι πᾶσαν ἐπὶ πᾶσιν ἀδιαφορίαν τε καὶ ἀσέβειαν ἐπεδείξαντο.
Μετ’ οὐ πολὺ δὲ κατασπῶσι καὶ τὸ τοῦ Μεγίστου Νεὼ καταπέτασμα ἐς μυρίας πολλάκις ἀργύρου μνᾶς ἀριθμούμενον, καὶ τούτου εὐροιζοτέρου παντός, καὶ εἰς βάθος χρυσῷ πυκαζόμενον.
Ἐπεὶ δὲ χρημάτων καὶ οὕτως ἐσπάνιζον (οὐδὲ γὰρ φιλοπλουτίας κόρον ὅτε δὴ τὸ βάρβαρον ἴσησι) τοῖς χαλκοῖς ἐποφθαλμίζουσιν ἀνδριᾶσι καὶ παραδιδόασι τούτους πυρί.
Ἥ τε οὖν ἐν τῇ Κωνσταντινείῳ ἀγορᾷ ἱσταμένη πολύχαλκος Ἥρα κέκοπται εἰς στατῆρας καὶ χωνείᾳ παραδίδοται, ἧς ἡ κεφαλὴ μόγις τέτρασι βοῶν ὑποτρόχοις ζεύγμασιν ἐς τὸ μέγα παλάτιον ἀποκεκόμισται.

Van Dieten, J. (ed.), Nicetae Choniatae historia (CFHB 11, Berlin 1975), pp. 647-648.

Geoffroy de Villehardouin describes the burning of Constantinople before its fall:

(247). En cette nuit, devers l'héberge de Boniface le marquis de Montferrat, je ne sais quelles gens qui craignaient que les Grecs ne les assaillissent, mirent le feu entre eux et les Grecs. Et la ville commença à s'éprendre et à s'allumer très durement; et elle brûla toute cette nuit et le lendemain jusqu'à vêpres. Et ce fut le troisième feu qui fut en Constantinople depuis que les Francs vinrent au pays; et il y eut plus de maisons brûlées qu'il n'y en a dans les trois plus grandes cités du royaume de France.

Geoffroy de Villehardouin, La conquête de Constantinople IΙ:247, ed. E. Faral (Paris 1973).

Nikephoros Gregoras writes of the fragmentation of the Byzantine Empire because of the fall of Constantinople to the Crusaders in 1204:

Τῆς γὰρ τοι Κωνσταντινουπόλεως ὑπὸ τῶν Λατίνων ἁλούσης, συνέβη τὴν τῶν Ῥωμαίων ἡγεμονίαν, καθάπερ ὁλκάδα μεγάλην, ἀνέμοις ἀγρίοις καὶ κύμασι θαλαττίοις συνειλημμένην, κατὰ τεμάχια καὶ μέρη πλεῖστα διαιρεθῆναι, καὶ ἄλλον ἄλλοθι κατὰ μόρια, καὶ ὡς ἕκαστοι τύχοιεν, ταύτην διαλαχόντας κληρώσασθαι, ἕως ὀψὲ καὶ μόλις περὶ τῆν Νικαέων μητρόπολιν ἀναγορευθῆναι συμπέπτωκε βασιλέα Θεόδωρον τὸν Λάσκαριν, τριακοντούτη ἤδη τυγχάνοντα.

Schopen, L. – Bekker, I. (ed.), Nicephori Gregorae historiae Byzantinae 1 (Corpus Scriptorum Historiae Byzantinae, Bonn 1829), p. 13.

The destruction of Galata by the fires ignited by the crusaders during the first siege of Constantinople:

The suburb of Galata or Pera to the north of the Golden horn was the first area of Constantinople to suffer from destruction. The dense Jewish neighborhoo, located on the slope facing the walled city, close to the Galata tower, was consumed by fire early in July 1203. Contemporary sources emphasize the destruction of Jewish houses, yet we may safely assume that many structures of their Greek neighbors were also lost. Several large fires swept through Constantinople proper. The north-western section of the city was damaged on 17-18 July 1203, yet various buildings of the residential area of Petrion survived. Around or probably on 18 August 1203, the premises of Pisan and Amalfitan settlers located between the Golden horn and the northern city wall were destroyed by the urban mob. On 19 August, some Latins crossed the Golden Horn and attacked the Muslim mitaton located close to the church of St. Irene, which stood between the Pisan and the Venetian quarters. While retreating, they set fire to several buildings in the vicinity. For two days and two nights the blaze spread eastward and southward through the most populous regions of Constantinople, in which craft and local trade were also concentrated. the last fire ignited by the Crusaders extended on 12-13 April 1204 along a section of the Golden Horn from a place to the east of the monastery of Christ Evergetes to the Droungarios, stopping at the western edge of the Venetian quarter which was thus entirely preserved.

Jacoby D., "The Urban Evolution of Latin Constantinople (1204-1261)", in Necipoğlou, N. (ed.), Byzantine Constantinople. Monuments, Topography and Everyday (Leiden – Boston – Köln 2001), pp. 278-280.

Prophecies associated with the fall of Constantinople to the crusaders:

a. ἀναστήσονται... γενεαὶ πικραί, ξανθαὶ καὶ πονηραὶ ἐν τῇ ἑπταλόφῳ καὶ ἀφανίσουσιν τὰς ἐκκλησίας τοῦ Θεοῦ, καὶ κυριοῦσιν τὸν ἄζυμον, καὶ φεύξονται ἀπ'αὐτῶν ἐκ τοῦ ἱερατικοῦ τάγματος τῶν τοῦ Θεοῦ ἐκκλησιῶν καὶ τῶν μοναχῶν οὐκ ὀλίγοι.

Maisano, R. (ed.), L'Apocalisse apocrifa di Leone di Constantinopoli (Naples 1975), pp. 70-1.

b. οὐαί σοι, ἑπτάλοφε Βαβυλών, ὅτι οὐ χιλιάσεις· διὸ καὶ οὐαὶ φῶ ἐπὶ σοί, ὅτι κρατήσει τὸ ἀγγελόνυμον σκῆπτρον μετὰ τοῦ μείρακος καὶ πυρροῦ ἔθνους ἀνερχομένου.

Pertusi, A., Fine di Bisanzio fine del mondo, p. 55, cited by Magdalino, P., «Prophecies on the Fall of Constantinople», in A. Laiou (ed.), Urbs Capta (Παρίσι 2005), p. 44 and n. 19.

The suburb of Galata or Pera to the north of the Golden horn was the first area of Constantinople to suffer from destruction. The dense Jewish neighborhoo, located on the slope facing the walled city, close to the Galata tower, was consumed by fire early in July 1203. Contemporary sources emphasize the destruction of Jewish houses, yet we may safely assume that many structures of their Greek neighbors were also lost. Several large fires swept through Constantinople proper. The north-western section of the city was damaged on 17-18 July 1203, yet various buildings of the residential area of Petrion survived. Around or probably on 18 August 1203, the premises of Pisan and Amalfitan settlers located between the Golden horn and the northern city wall were destroyed by the urban mob. On 19 August, some Latins crossed the Golden Horn and attacked the Muslim mitaton located close to the church of St. Irene, which stood between the Pisan and the Venetian quarters. While retreating, they set fire to several buildings in the vicinity. For two days and two nights the blaze spread eastward and southward through the most populous regions of Constantinople, in which craft and local trade were also concentrated. the last fire ignited by the Crusaders extended on 12-13 April 1204 along a section of the Golden Horn from a place to the east of the monastery of Christ Evergetes to the Droungarios, stopping at the western edge of the Venetian quarter which was thus entirely preserved.

Jacoby D., "The Urban Evolution of Latin Constantinople (1204-1261)", in Necipoğlou, N. (ed.), Byzantine Constantinople. Monuments, Topography and Everyday (Leiden – Boston – Köln 2001), pp. 278-280.

Prophecies associated with the fall of Constantinople to the crusaders:

a. ἀναστήσονται... γενεαὶ πικραί, ξανθαὶ καὶ πονηραὶ ἐν τῇ ἑπταλόφῳ καὶ ἀφανίσουσιν τὰς ἐκκλησίας τοῦ Θεοῦ, καὶ κυριοῦσιν τὸν ἄζυμον, καὶ φεύξονται ἀπ'αὐτῶν ἐκ τοῦ ἱερατικοῦ τάγματος τῶν τοῦ Θεοῦ ἐκκλησιῶν καὶ τῶν μοναχῶν οὐκ ὀλίγοι.

Maisano, R. (ed.), L'Apocalisse apocrifa di Leone di Constantinopoli (Naples 1975), pp. 70-1.

b. οὐαί σοι, ἑπτάλοφε Βαβυλών, ὅτι οὐ χιλιάσεις· διὸ καὶ οὐαὶ φῶ ἐπὶ σοί, ὅτι κρατήσει τὸ ἀγγελόνυμον σκῆπτρον μετὰ τοῦ μείρακος καὶ πυρροῦ ἔθνους ἀνερχομένου.

Pertusi, A., Fine di Bisanzio fine del mondo, p. 55, cited by Magdalino, P., «Prophecies on the Fall of Constantinople», in A. Laiou (ed.), Urbs Capta (Παρίσι 2005), p. 44 and n. 19.