The term phyletism from phili: race or tribe was coined at the Holy and Great pan-Orthodox Synod that met in Constantinople in 1872. The meeting was prompted by the creation of a separate bishopric by the Bulgarian community of Constantinople for parishes only open to Bulgarians. It was the first time in Church history that a separate diocese was established based on ethnic identity rather than principles of Orthodoxy and territory. Phyletism, however, should not be confused with nationalism (which was known at that time as φιλοπατρία) as the latter simply means devotion and loyalty to one's nation and/or culture and is not at odds with Orthodoxy.
Here is the Synod’s official condemnation of ecclesiastical racism, or “ethno-phyletism,