sentences:  The 1853 constitution guaranteed religious freedom, and the country had vast, unpopulated land reserves.Under President Domingo F. Sarmiento, a policy of mass immigration was encouraged; it provided relief to refugees fleeing the violent pogroms in the Russian Empire in 1881.Jewish agricultural settlements were established in the provinces of Buenos Aires (Lapin, Rivera), Entre Ríos (San Gregorio, Villa Domínguez, Carmel, Ingeniero Sajaroff, Villa Clara, and Villaguay), and Santa Fe (Moisés Ville).