Documentary postcard – a postcard with images of important historical events, ceremonies, political and artistic events, photos from places of natural disasters, military campaigns and battles. Documentary postcards were especially popular in the difficult war and revolutionary years. So, during the Russo-Japanese War photographers of the Community of Saint Eugenia made a lot of pictures of the equipment of the army, scenes of battles, soldiers, etc. During the revolution and the first years of Soviet power photo-postcards with scenes of street fights, various festivities and ceremonies — funerals, anniversaries, etc. — were actively published