Russian conscription uniquely required Jewish recruits to convert to Orthodoxy

Evidence

Whereas most state authorities had largely given up in the eighteenth century on making Muslim conversion to Christianity an official priority, they continued to hold out hope for the conversion of the Jews. Thus Nicholas saw military service as a gateway to the tsar’s faith. In 1827, he introduced conscription for Jewish communities. Unlike Muslim and other non-Orthodox conscripts, these inductees into the Russian army were expected to become Orthodox Christians (Jews were also denied promotion to the rank of officer). — James Renton, Ben Gidley (eds.), Antisemitism and Islamophobia in Europe, 520