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This entry was originally written by Dwight A. Radford for Red Book: American State, County, and Town Sources.
Most of the foreign immigrants who settled in Montana arrived through the port of New York, although immigrants also came from Canada. The ports of entry from Canada were Sweetgrass, Gateway, and Roosville. Sweetgrass was established as a port of entry in 1903, Gateway in 1908, and Roosville in 1930.
The Montana ports of entry are filed with the Seattle passenger lists, which have been microfilmed and are at the National Archives and the FHL. Additional information on persons entering through Montana ports-of-entry may be found in the St. Albans, Vermont District records (so-called, see Vermont Immigration), which are indexed.