Pianist, composer, and arranger Mary Lou Williams (1910-1981) is often referred to as the First Lady of Jazz in the annals of American music history. Williams was a highly respected musician in her day whose repertoire spanned several seminal jazz styles, from boogie-woogie to bebop, and she was an integral member of what became known as the Kansas City big-band sound during the 1930s. In her later years she wrote jazz-inflected liturgical works for Roman Catholic masses and taught at Duke University. Williams, remarked Denver Post writer Glenn Giffin, "was the first, for a long time the only, and many claim the most significant, woman in jazz between the era of the '20s and her death in 1981."