Born in Oppido Lucano, Italy. At birth given the name Johannes. In 1102 converted to Judaism, and in order to further his study of Judaism traveled to Constantinople, Baghdad, and Palestine, finally settling in Egypt and becoming a member of the thriving Jewish community situated there, where he wrote his memoirs. Obadiah's writings contain the earliest surviving manuscript source of Jewish music notation of synagogue chant.
Sources: Encyclopedia Judaica, Grove Music Online.