This article deals with an important source which has recently been recovered in the State Archives in Lublin. It is a register with entries documenting the death of several Uniate Christians at Pratulina (Podlasie) on 26 January 1874. The incident happened when a crowd of local people tried to prevent an Orthodox cleric from taking over their church. His escort of Russian soldiers fired at the crowd and killed thirteen men. In the interwar period the original register of the Pratulina parish went missing; later a duplicate copy disappeared as well. Now, however, it has been found in the Lublin Archives collection of Orthodox parish registers. Later, the Uniates whose deaths are recorded in the register had their martyrdom acknowledged by the Church. The thirteen entries, written as the rest of the register in Russian, contain surnames and Christian names of the victims (they are given in their Polish and Russian versions), precise indication of the time of their death (day and hour), as well as their age and family status. The records suggest that nine men must have died at the scene of the incident, in front of the church, and four of the wounded died soon afterwards in their homes. The author of this article has also seen the register of the Uniate parish of Drelów where a similar incident happened on 17 January 1874 resulting, on the testimony of that book, in one death. Traditional accounts, later repeated in literature, put the number of deaths at Drelów at five, or even thirteen. The divergence needs to be cleared up. So far, the strong evidence of register entries indicates that confrontations with the Russian military at Pratulina and Drelów cost 14 lives.