Who was the first woman to be commemorated on a U.S. postage stamp?

The first woman to be commemorated on a U.S. postage stamp was the wife of the first president.

This did not happen until the twentieth century.

In 1901, Martha Washington was commemorated on the 8-cent stamp.

In 1918, she was pictured on the 2-cent prepaid postcard; in 1920, on the 4-cent stamp; and in 1938, on the 1/2-cent stamp.