If you cannot locate relatives who are interested in your ancestor, have you at least tried and contacted other genealogists who are researching in the same location?
While they might not be related, they might have ideas for sources or repositories where you should conduct your research. Others might know what records have been microfilmed or digitized, etc.
Don’t just limit yourself to trying to find relatives–others with similar areas of research may be able to help you even more.
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