Cavalry Use of Pistols?

Here’s a subject I don’t know much about, and I’m hoping some of the folks reading this can help educate me: cavalry use of handguns. How many groups actually experimented with handguns as a primary armament for cavalry troops? Were they just backup weapons? Were mounted soldiers expected to be able to fire carbines accurately while mounted, as opposed to using they horses simply to get to a point on the field and then dismount and fight as infantry (ie, dragoons)?

It seems like people would have considered the possibility of one-handed shooting with handguns from the saddle (including both older flintlock/wheellock era guns and early 20th century cartridge guns), but I don’t know if anyone actually did. I am told that this was the primary use for the Steyr 1907 selfloader, but corroborating that has been difficult.

The question came to mind when I was looking for information on the JoLoAr I just recently purchased. Apparently the single largest order of those pistols went to Peruvian mounted police. The JoLoAr’s defining characteristic, of course, is its ease of use single-handed, for the mounted shooter. I have not been able to determine, though, if those police units were armed exclusively with JoLoAr pistols or if they were supplemental to a carbine.

So, if anyone can help educate me on this, I would appreciate it! Any book recommendations on the subject would be very helpful too – thanks!