Page "American English" Paragraph 6

Most North American speech is rhotic, as English was in most places in the 17th century.

Rhoticity was further supported by Hiberno-English, West Country English and Scottish English as well as the fact most regions of England at this time also had rhotic accents.

In most varieties of North American English, the sound corresponding to the letter r is an alveolar approximant or retroflex rather than a trill or a tap.

The loss of syllable-final r in North America is confined mostly to the accents of eastern New England, New York City and surrounding areas and the coastal portions of the South, and African American Vernacular English.