Here's a question for the first time-travelling Sherlockian to get around to at some point: Could we have had Sherlockiana without the Roaring Twenties?
The 1920s were a virtual primordial soup of Sherlock Holmes fandom.
We often think of that time as all flappers, jalopies, bathtub hooch, and jazz. A period of prosperity between World War One and the Great Depression, the 1920s saw Art Deco and Al Capone, movie theaters and baseball stadiums. Things were definitely not the Victorian era any more, in some very big ways.
And in the world of the Sherlock Holmes fan, who had yet to club together with any fellow fans, it was an amazing time as well. Conan Doyle was still alive, and the stories we now know as The Casebook of Sherlock Holmes were being trickled out over that decade, seeming almost as a reluctant fan service. William Gillette had already made his play Sherlock Holmes a hit, with a Sherlockian like Gray Chandler Briggs of St. Louis happily having seen it eleven times, and revival tours were happening throughout the decade.
Eille Norwood was the Benedict Cumberbatch of his day, coming out in forty-seven Sherlock Holmes films that actually set Sherlock Holmes in the 1920s, with cars and telephones. And these were Holmes movies that Sir Arthur Conan Doyle actually went to a movie theater and watched at least one of. It was a decade of celebrity celebrated, and both Doyle and Holmes where solidly in their celebrity by the Twenties.
Sherlockiana as the old school Sherlockians know it came out of the 1930s. The big clubs formed. Books were published. Letters were written. (Hey, letters used to be the bloodstream of the Sherlockian world, kids. Do not diminish the importance of letters.)
But the Roaring Twenties . . . that's when the tires that motorcar Sherlockiana would drive on were being inflated, the gas tank filled, the crankcase oiled. Had the Great Depression happened immediately after World War One, with no Twenties in between, who knows what path Holmes might have taken?
If those time-travelling Sherlockians I conjectured in the first bit ever get to messing about too much, maybe we'll find out one day. But until then, I think we have to give that decade a little credit.