On August 24, 2000, the United States Postal Service released the 10-cent Stilwell stamp as part of the Great Americans Series, begun in 1980. Its appearance differed so dramatically from earlier stamps in the series that collectors thought a new series had begun. The USPS had independently reached the same conclusion and named it the "Distinguished Americans Series." This evolution followed a tradition begun with Famous Americans (1940), Prominent Americans (1965-1978) and Great Americans (1980-1989), and, finally, the Distinguished Americans.
Illustrator Mark Summers gave the Distinguished Americans Series its new look. He used a scratchboard technique, in which the artist begins with a completely black surface and scratches away the unwanted color, leaving the remaining lines and shapes to form the final picture. Summers illustrated the first twelve stamps released in the Distinguished Americans Series.
References:
Kloetzel, James E., ed. 2009 Specialized Catalogue of United States Stamps and Covers. 87th ed. Sidney, Ohio: Scott Publishing Co. 2008.
