Benjamin West's c. 1788 painting of "King Lear" does not look like the work of an American painter. West's use of color and emphasis on movement and the focus on antagonist vectors (of both line and form) in the painting connect it to a European Baroque past even as they begin to suggest the faintest glimmers of a Romantic future. Although most European painters by the last decades of the 18th century had abandoned a Baroque style to shift in Romanticism and thus away from the grand, lofty and (so the Romantics would argue) in key ways anti-humanist elements of Mannerism and Baroque art, in the New World American painters were still basing their visions on the already dying style of the Baroque and West himself was not entirely free from that trap.
Ironically, West himself had no small influence on British painters (quite unusual for an American artist of his generation). As a painter of historical subjects to George III and one of the founders in 1768 of the Royal Academy (he would serve as the Academy president after Sir Joshua Reynolds) he served as a model to a number of British painters, even as his style borrowed heavily from French and Italian Baroque traditions (which were in turn, of course, based upon Mannerist traditions of painting)(Encyclopedia Britannica, Benjamin West).
Baroque style began in France and indeed the word stems from the French word "rocaille", which translates as "rockwork" and referred to the elaborate, curvilinear designs that were used by early French Rococo artists to create the effect of shell-strewn mythical grottos. The specific reference was soon extended to the general use - in architecture and fine arts such as painting and sculpture as well as in the decorative arts - of curved ornamentation that was drawn from natural forms such as shells or flowers. Beyond these curved, natural forms, Rococo art and design was distinguished by a lightness of mood and daintiness of execution that ranged fr...