There was a program called the Industrial Removal Office that was created to encourage Jewish immigrants to move out into the country. The program provided the fare to relocate the people and had contacts to set the immigrant up with a job. My grandfather went to Detroit and worked at Ford for a while and then returned to NY. The Center for Jewish History has a database of those that went west with the IRO. https://genealogy.cjh.org/familycollections.php
The other possibility is that some people from the same town had settled in St. Louis and that's why he went there.
Secaucus NJ USA
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