Prolog. An Old Ukrainian expanded version of the Greek Synaxarion, which is a collection of lives of saints for every day of the year. The name is derived from the introduction (prólogos) to the Synaxarion, which was translated into Church Slavonic in the early 12th century. Prolog is three times larger than its prototype; it includes additional lives of Slavic and Rus’ saints (eg, Saints Borys and Hlib and Saint Theodosius of the Caves) and other religious and edifying material taken from Byzantine religious and secular sources, the patericons, and the Rus’ Primary Chronicle. Two Ukrainian redactions exist. The first dates from the early 13th century. The second is believed to have been the work of Cyril of Turiv. Prolog was used widely as a book of knowledge and served as the foundation for didactic literature in Kyivan Rus’. Mykola I. Petrov's book about it was published in Kyiv in 1875.

[This article originally appeared in the Encyclopedia of Ukraine, vol. 4 (1993).]