Part of Constantinople on the web section of Elpenor's history resources [15 Pages]
In the years which followed the conquest Latin priests were sent to Constantinople from France, Flanders, and Italy, to take charge of the churches in the city. These priests appear to have been great hunters after relics. Thus it came to pass that there was scarcely an important church or monastery in most Western countries which did not possess some share of the spoil which came from Constantinople.
For some years the demand for relics seemed to be insatiable, and caused fresh supplies to be forthcoming to an almost unlimited extent. The new relics, equally with the old, were certified in due form to be what they professed to be. Documents, duly attested and full of detailed evidence—sometimes, doubtless, manufactured for the occasion—easily satisfied those to whom it was of importance to possess certified relics, and throughout the West the demand for relics which might bring profit to their possessors continued to increase. At length the Church deemed it necessary to put a stop to the supply, and especially to that of the apocryphal and legendary acts which testified to their authenticity, and in 1215 the fourth Lateran council judged it necessary to make a decree enjoining the bishops to take means to prevent pilgrims from being deceived.
Reference address : https://www.ellopos.net/elpenor/greek-texts/fathers/pears-constantinople-1204.asp?pg=14