MOISÉS VILLE, Argentina — At its height in the 1940s, this outpost on Argentina’s grasslands had four synagogues for a population of 5,000, a theater for Yiddish-language acting troupes, a newspaper filled with feverish debates about the creation of the state of Israel and saloons where Jewish gauchos galloping in from the pampas could nurse a drink alongside fellow cowhands.

Now, Moisés Ville, founded in 1889 by Jews fleeing the pogroms of the Czarist Russian empire, has only about 200 Jews among its 2,000 residents. The last regularly functioning synagogue lacks a rabbi. The Hebrew school halted classes this year because of the dwindling number of Jewish children. Some of the last remaining Jewish gauchos have swapped their horses for Ford pickup trucks, and they now ponder the future of their way of life.

“There are various types of gauchos: those who look for trouble; those who are valiant soldiers; those who meekly take orders,” said Arminio Seiferheld, 70, who owns a small herd of Braford cattle and lives in a modest house shaded by palm trees. His leathery skin attests to a lifetime spent roaming the plains in harsh weather.

“I’m the type of gaucho who is still here, a survivor in a place where we once thrived,” he said, dressed in bombachas, the loosefitting pants worn by Argentina’s horsemen. His parents, Jews who fled Nazi Germany in the 1930s, made their way to Moisés Ville when it was a linchpin for more than a dozen Jewish farming colonies scattered across Argentina’s grassy plains, known as the pampas.