In order to provide some background material for the Orientale Lumen Conferences in 2010, with the help of Father Michael Hayduk, I prepared a summary of the first Seven Ecumenical Councils that I post here.

SITE: Nicaea
YEAR: A.D. 787
POPE: Hadrian I, 772 – 795
EMPERORS: Constantine VI, 780 – 797 and Empress Irene (797 – 802)
ACTION: This council, called by Empress Irene (widow of Emperor Leo IV and regent for her son Constantine VI), with its doctrinal decree ratified by Pope Hadrian I, condemned ICONOCLASM. The Pope’s epistle here, just as with Pope St.Leo I at Chalcedon, set the tone of the council.
NOTE: Brewing beneath the surface at this time, however, was a rejection of papal authority. The Eastern Bishops, cut off from Rome and receptive to heresy under persecution, were held suspect by Rome.
NOTE: Iconoclasm had been fostered by Emperor Leo III (717 – 741), who was opposed by Popes Gregory II (715 – 731) and Gregory III (731 – 741) and by St. John Damascene (d.749), priest and Doctor of the Church, who published three discourses in defense of images.
HERESY: ICONOCLASM.

The Second Council of Nicaea was convoked by Emperor Constantine VI and his mother Irene, under Pope Adrian I, and was presided over by the legates of Pope Adrian; it regulated the veneration of holy images. Between 300 and 367 bishops assisted.