Casimir Johannes Ludwig Otto, Prince of Sayn-Wittgenstein-Berleburg (22 January 1917 – 21 February 2010) was a German nobleman, businessman and politician from the Christian Democratic Union.
He was Member of the European Parliament from 1979 to 1983.
[1] Sayn-Wittgenstein-Berleburg was CDU treasurer during the CDU donations scandal.
[2] He was stepson of Richard Merton [de] and father-in-law of Wolfgang-Ernst, Prince of Ysenburg and Büdingen.