He became an unabashed Impressionist during his long training in Europe, and was a great painter by any standards.
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He never aspired to be an impressionist, but painted many works plein air, with loose brushwork, and conveying impressions.
Whistler developed a unique style which had much in common with the Impressionists, anticipating several of the key features of Impressionism.
Today, many consider him to be the father of American landscape painting.
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