Supremi disciplinae was a motu proprio released on 2 July 1911 by Pope Pius X that reduced the number of holy days of obligation within the Roman Catholic Church. It reduced the number of such non-Sunday holy days from 36 to 8."Supremi disciplinæ" in Catholic Encyclopedia The present list was established in 1917.Codex Iuris Canonici canon 1247 (1917).
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