Possibly the first RV. {LINK}

If we define a RV/ Recreational Vehicle as a motorized vehicle that is designed to provide lodging or camping quarters, they first appeared in the US, in 1904.
LINK WITH PHOTO.

Here’s another early RV, a custom built job for the president of Yellow Coach from 1929.

Not sure if I should laugh or cry.

The Travel Log is right up there when it comes to vintage RVs (1917)

Charles Kellogg’s Travel Log, handmade in 1917 from a fallen chunk of a redwood log and mounted on a 1917 Nash Quad truck, the toughest, most rugged vehicle of its kind at the time. From 1917-1921, Kellogg took his Travel Log on the road. He drove it across the country four times, coast-to-coast, bringing word of the redwoods to people who had never heard, let alone imagined, there could be such trees.