Edinoverie (Russian: Единоверие; also transliterated as Yedinoverie or Yedinoveriye) is an arrangement between certain communities of Russian Old Believers and the Russian Orthodox Church, whereby the communities are treated as a part of the mainstream Orthodox Church, while maintaining their own traditional rites. Thus, they are often described as Old-Ritualists (Russian: Старообрядцы, Staroöbriadtsy), rather than Old Believers.
The Russian word Edinoverie is a variation of the Russian word Edinovertsy, meaning "coreligionists" (literally, "ones of the same faith"), which also is used to refer to the members of the community.
During the latter part of the eighteenth century a movement of reconciliation developed between hierarchs of the Russian Orthodox Church and some communities of Old Believers who had not accepted the changes to the church rituals and translations of the Scripture begun under the leadership of Patr. Nikon during the 1660s. Edinoverie arrangements began during the time when Abp. Nikephoros Theotokis, Archbishop first of Slovansk and Kherson and later of Astrakhan and Stavropol, began to reach out to Old Believers in 1780. At the time Metr. Platon II, who as metropolitan of Moscow, was the first hierarch of the Church of Russia,
Nikifor, whose see was in Poltava the seat of the then Diocese of Sloviansk and Kherson in eastern Ukraine, visited a chapel of Popovtsy Old Believers in Elisavetgrad in July of that year. He offered the local Old Believers, who had priests of their own that were not recognized by the official church, the possibility of legalizing their chapel as an official church and integrating it into the established Church with a priest selected by the Old Believers themselves and using the pre-Nikonian service books and rites. The Old Believers of Elisavetgrad rejected the offer, but later that month, many Old Believers of the village of Bolshaya Znamenka accepted a similar offer. In February 1781, a letter was issued by the archbishop, authorizing them to set up a church legally and carry out their services in accordance with their traditional rites. That was done by consecrating as a church the wooden chapel that the Old Believers of Znamenka had built in 1776.
Nikifor's arrangement for legalization turned out to be very popular and soon not only did the Popovtsy begin to request legalization, but also the Bespopovtsy (priestless Old Believers) began asking Nikifor to provide them with priests. One such Bezpopovtsy community was the village of Zlynka in 1782. In same year the Edinoverie arrangement spread to the Upper-Isaac Skete in the Irgiz area of the Saratov Governate as merchants of Moscow and Volga arranged a similar legalization.
Having learned of the Edinoverie compromise, Old Believer monastics began to petition civil and ecclesiastical authorities of the Starodub district regarding legalizing priests of their Popovtsy. Monk Nikodim, with the agreement of many Popovtsy of the area and the support of Count Peter Rumyantsev-Zadunaisky was able, after many rejections, to get a petition to the Empress Catherine that she forwarded to the Holy Synod. In April 1784, Catherine issued a rescript legalizing priests for the Old Believers and authorizing them to conduct services in the Old Rite. The rescript, however, did not allow for any bishops, and subordinated the Edinoverie under the hierarchs of the Russian Orthodox Church. This disappointed Nikodim, who fell sick and died at the age of 29. The rescript was followed by a government decree, in August 1785, that provided for the organization of "Old Believer" churches with the established church, but again without provisions for their own bishops. Issuance of this decree, however, is considered the beginning of the Edinoverie movement.
During the reign of Emperor Paul I, the integration of Old Believers into the established church on acceptable terms continued. Old Believers in Kazan and in Nizhny Novgorod received legal priests in 1796 and 1797, respectively. On March 12, 1798, Paul I expanded the Edinoverie program through a decree that required all bishops to ordain priests for the Old Believer communities and while using the "old" rite, acceptable by the believers, for the ordination. His decree also authorized construction of churches for the Old Ritualists.
Metr. Platon II of Moscow, the first hierarch of the Church of Russia, wrote the "Eleven Articles of Edinoverie" (Russian: «11 пунктов единоверия»), the document that regulated the "union" between the official church and the Old Believers. Although the Metropolitan's rules satisfied some of the desires of the Old Believers, Edinoverie parishioners nevertheless remained second-class citizens within the Church: for example, the Old-Rite priests were normally not permitted to administer sacraments to the mainstream Orthodox believers
During the nineteenth century, the existence of the Edinoverie appeared more as toleration of a "necessary evil" and a means to return the "dissenters" to the established church. The Edinoverie program also provided the government with a wedge in relations with those Old Believers who were not part of the Edinoverie. The prohibition by the government on printing Old Ritualist religious books by anyone other than by the Edinoverie printing houses was an example. The consecration of the Edinoverie's first bishop, Bishop Simon (Shleev) of Okhta, took place in 1917, just before the Bolshevik takeover.
The majority of followers of the Edinoverie in the major cities of Russia were of the bourgeois and merchant classes that took active part in social and charitable work.
As with the established churches, the Edinoverie community was devastated during the soviet times and was not revived until 1990.