Question: The tune of "O Sanctissima" has been notably reused in the first half of a American civil rights anthem that is most commonly attributed as having descended lyrically from what hymn?
Sentence (from "O Sanctissima"): The earliest known publication was from London in 1792, presenting it as a traditional song from Sicily; but no original source or date has been confirmed for the simple melody or the poetic text.
Relevant evidence: No