[citation needed] Lazar Poptraykov was born in Dambeni, Ottoman Empire (now Dendrohori, Greece) on 10 April 1878.

[13] He finished the Bulgarian Men's High School of Thessaloniki in 1898,[14] though he had started touring the Kastoria region to promote the work of IMARO two years earlier, in 1896.

[9] Poptraykov was arrested by Ottoman authorities and imprisoned in Korçë along with fellow revolutionaries Manol Rozov, Maslina Grancharova, and Pavel Christov.

Poptraykov died at the end of the Ilinden Uprising when he was assassinated by Konstantinos Christou, a fighter for Greek interests and was acting under orders by Germanos Karavangelis, bishop of Kastoria.

[17] Christou who switched the side from Bulgarians to Greeks and vice versa, was received back by the IMRO at the insistence of Poptraykov.