Check.Church

Old Calendarists

Eastern Orthodox · 1924–1935 · Greece; Romania; Bulgaria; Cyprus; diaspora

Traditionalists who broke communion over the 1924 calendar reform — holding that only an ecumenical council could alter what one had fixed. Precision matters: keeping the Julian calendar is not Old Calendarism (the ROC keeps it in full communion); the fork is severed communion, and the movement has since fragmented into many rival synods.

Old Calendarists was formed between 1924 and 1935, as a process rather than a single event. Old Calendarists continues today. Old Calendarists's institutional line runs back through Church of Greece, Eastern Orthodoxy to the post-apostolic church. No body on this tree is the assembly of Acts 2; where a body claims that, the claim appears in the claimed-lineage layer.

Between the post-apostolic church and Old Calendarists stand 2 divisions along the institutional line, counting separations and disputed forks, not mergers, renewals or national organizations.

At a glance

Formed
Between 1924 and 1935, as a process rather than a single event
Family
Eastern Orthodox
Region
Greece; Romania; Bulgaria; Cyprus; diaspora
Key figures
Chrysostomos of Florina, Matthew of Bresthena
Cause tags
Doctrine, Governance
Also known as
Genuine Orthodox Christians; True Orthodox

What it separated from

On the tree

Old Calendarists and its institutional line back to the post-apostolic churchAD 33The church at Pentecost: On divine groundThe church at Pentecost: on divine groundtoday100424431451105418501924The post-apostolic church (The spine)The post-apostolicchurchDepartureChurch of the East (Church of the East)Church of the EastChurch of the EastThe conciliar church (The spine)The conciliar churchDepartureThe Chalcedonian church (The spine)The Chalcedonian churchDepartureOriental Orthodoxy (Oriental Orthodox)Oriental OrthodoxyOriental OrthodoxEastern Orthodoxy (Eastern Orthodox)Eastern OrthodoxyEastern OrthodoxRoman Catholicism (Catholic)Roman CatholicismNot gatheredChurch of Greece (Eastern Orthodox)Church of GreeceEastern OrthodoxOld Calendarists (Eastern Orthodox)Old CalendaristsEastern Orthodox

Solid lines are separations and unions; dashed lines are renewals that began inside a body; dotted gray lines are national organizations of one communion; a diamond marks a fork event where neither side is drawn as the one that left. Every line runs back to the post-apostolic church; no body descends from the assembly of Acts 2. Dashed gray boxes mark the institutional line after the apostles, shown as departure; no line of descent is drawn from Pentecost. A verdict appears on a box once its section is published.

Sources

Research compiled July 2026. Page data built 2026-10-31.