As material for tasks the real historical events, facts, military leaders, scientific and political figures, are taken. Only a few personages are invented. A reader knows them without effort. Complication of mathematical tasks is neat so that material either studied or was already studied on the lessons of mathematics. In this connection at decision tasks from this book there is magnificent possibility to kick about a "bridge" between by mathematics and history, it is better to memorize material and widen an outlook.