According to THIS there was Morris dancing in early American. The author is quite open about hoping someone will do more research to back up what he has written. Here's a relevant snippet:

An American branch of the English Folk Dance Society (later the English Folk Dance and Song Society) was founded in 1915; it later became the Country Dance Society (and later yet, the Country Dance and Song Society). At dance camps sessions in Amherst, Massachusetts and, subsequently, at Pinewoods Camp in Plymouth, Massachusetts (more irony: Plymouth was where the Pilgrims settled), CDSS has been teaching morris dancing for many years: at least since the mid-1950s at Pinewoods, and perhaps as early as the 1930s or earlier in Amherst.