Did Americans in 1776 have British accents?

(nicholasjohnpatrick.com) Reading David McCullough’s 1776, I found myself wondering: Did Americans in 1776 have British accents? If so, when did American accents diverge from British accents?
The answer surprised me. Continued

Image: Miss Carolina Sulivan - one of the obstinate daughters of America, 1776. Cartoon shows Sullivan's Island, portrayed as a head-and-shoulders portrait of a woman who looks like William Pitt, right profile, with large hairdo meant to conceal fortifications, cannons, and several battle flags. (Library of Congress)