 Upon his return to Moscow , Lissitzky attended the Polytechnic Institute of Riga , which had been evacuated to Moscow because of the war , and worked for the architectural firms of Boris Velikovsky and Roman Klein . During this work , he took an active and passionate interest in Jewish culture which , after the downfall of the openly antisemitic Tsarist regime , was experiencing a renaissance . The new Provisional Government repealed a decree that prohibited the printing of Hebrew letters and that barred Jews from citizenship . Thus Lissitzky soon devoted himself to Jewish art , exhibiting works by local Jewish artists , traveling to Mahilyow to study the traditional architecture and ornaments of old synagogues , and illustrating many Yiddish children 's books . These books were Lissitzky 's first major foray in book design , a field that he would greatly innovate during his career . 
