I remain dubious that Twain attained much recognition in Europe because
of the Jumping Frog tale, as it is very much regional humor - but of
such quality that it garnered national recognition.  I suspect that it
was The Innocents Abroad that earned him, at least, Europe's attention.
 I'm wondering if any of his letters to Alta California found their way
into European publications.  Is it possible that these columns caught
the attention of those Europeans residing in the US; ambassadors,
business representatives, etc. that may have forwarded the articles to
their homelands.  Their interest may have been piqued by this
provocative journalist making unusual observations of their country(s).
How successful was initial publication of The Innocents Abroad abroad?
It appears that the French version of the Jumping Frog came out
following publication of The Innocents Abroad.

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