Complex sentence: Ottoman Armenians educated with the European Way began to make attempts in forming organizations--secret societies, local groups, such as the'Protectors of the Fatherland' (1881) which was established in Erzurum.
Split into simpler sentences: Ottoman Armenians educated with the European Way began to make attempts in forming organizations--secret societies, local groups. In 1881, the'Protectors of the Fatherland', was established in Erzurum.