in Grecian Antiquity, the general assembly of Athenian citizens, who met from time to time to discuss public affairs. Ecclesia were of two kinds, ordinary and extraordinary. The first of these were held three times every month; while the others were only summoned on some pressing emergency. When any measure of unusual importance was to be publicly debated, the people were summoned from the country by special messengers. An assembly thus convened was called a catacleisia.

Much discussion has taken place as to the exact days of the month on which the ecclesia were held; but the result has only been to prove either that there were no days invariably fixed for them, or that we have no data by which to determine accurately what these days were. In Ulpian it is stated that when there were three assemblies a-month, the first fell on the eleventh, the second on the twentieth, and the third about the thirtieth of the month.

Ecclesia were originally held in the Agora or Forum. The place of meeting was subsequently removed to the Pryx, and afterwards to such of the greater temples as might be most convenient. The Pryx lay to the west of the Areopagus, and commanded an extensive view. It was partly within the city walls, and had an area of about 12,000 square yards. On its northern side, cut out of the solid rock, was the bema or hustings from which the speakers addressed the people. From this tribunal a splendid view of the principal buildings of the city might be had. The right of assembling the people lay with the presidents of the senate or Council of Five Hundred, who both advertised beforehand the business to be discussed, and on the day of meeting sent round a crier to remind the citizens that their presence was required. In times of war, however, or other national crises, the generals of the army sometimes assumed this privilege, though it was necessary for them in doing so to give notice of their intention by a public proclamation. They also sometimes claimed the right of preventing the ecclesia from assembling; but their claims to this privilege were not generally recognised. Such of the citizens as refused to attend were fined, and six magistrates called Lexiarchs were appointed to collect the fines. To assure a full meeting, the custom was ultimately introduced of paying the poorer classes a small sum for their attendance. This sum was originally an obolus, but after the time of Pericles it was raised to three.

Ecclesia is also the name in Hellenistic Greek for the Christian Church.