I recently visited Rockingham County, Virginia, in the Shenandoah Valley (in the vicinity of James Madison University), where there is a sizable Old Order Mennonite (technically not Amish, apparently) community that uses horses and buggies. One thing that I did notice was that none of the buggies had license plates (nor did the Amish ones in Lancaster County, PA that I saw a while back), though at first that didn’t seem odd because other “vehicles” like bicycles don’t always have to have license plates, but I got to thinking - is there any jurisdiction that imposes registration requirements, or requirements to display evidence of registration like a “license plate” on horses or horse-drawn vehicles in order for them to be used on public streets? Are the buggies I saw technically registered with (or required to be registered with) the State of Virginia or Rockingham County but evidence of the registration is not required to be displayed publicly?
I recall learning somewhere (yeah, not a good source) that license plates got started with the rise of automobiles because the automobile was a lean mean killing machine compared to former vehicles and hit-and-run incidents became a serious concern, so the law had to come up with a way to let bystanders identify just who it was that ran them over and then ran.
I already know that buggies can generally use, in theory, any public road here in Virginia except interstates and other controlled-access highways that are explicitly marked with signs forbidding them. For example, onramps to I-95 have a sign that bans “animals”, which I believe includes horseback riding and to horse-drawn vehicles.
It seems that a basic web search turns up a number of sources that state that there is no equivalent to a “driver’s license” for riding horses or driving horse-drawn vehicles in many areas of the US. Remember that driver’s licenses and car registrations/license plates are separate, at least in the US.