Petros III may refer to:
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Pope Peter III of Alexandria
Pope Peter III of Alexandria also known as Peter Mongus (from the Greek μογγός ''mongos'', "stammerer") was the 27th Pope of Alexandria and Patriarch of the See of St. Mark.
Biography
After the Council of Chalcedon, Peter Mongus was an ar ...
, ruled in 477–489
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Michael Petros III Kasparian
Michael Petros III Kasbarian (in Armenian Միքայէլ Պետրոս Գ. Գասպարեան ) was a member of the Order of St. Antoine, from Aleppo, Syria.
During his time at Bzommar there was not a church. All the big events took place at the ...
, ruled in 1753–1780
{{hndis, Petros 03