Chizhevsky was born in the town of Tsekhanovets (Ciechanowiec in Polish) in Grodno Governorate of the Russian Empire (now Poland). His father Leonid Vasilievich Chizhevsky was a Russian military general. He spent his early years, and later his teenage years, in Kaluga. As a youth he met Konstantin Tsiolkovsky, a noted space scientist, who also lived in Kaluga. Chizhevsky was educated at the private modern school of F. Shakhmagonov. In 1915 he spent his summer observing the sun and first hypothesized the effect of periodic changes in solar activity on the organic world. In 1916 he entered World War I as a Russian, fighting on the Galician front and earning a Cross of Saint George. There he observed directly that battles tended to wax and wane with the strength of solar flares and geomagnetic storms during the concurrent height of solar cycle 15.