The Niš conspiracy was a failed attempt of a rebellion in Niš in 1821, revealed by the Ottomans the same year.
It was led by the Niš Secret Organization, created in 1820 by Orthodox priest Meletius, who was a Greek.
[1] It was influenced by the Greek revolutionary organization, Filiki Eteria (Society of Friends).
[1] At the end of 1820, the Nis Secret Organization sent its representative to Constantinople, "who was in the patriarchate for 2 to 3 months" as "the envoy of the Bishop of Nis".
[1] After revealing of the conspiracy by the Ottomans, Father Meletius along with 5 other priests and laity, was hanged on charges of complicity in the Wallachian uprising of 1821.