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In page Wilhelmus:

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The song „Wenn alle untreu werden“ ("When All Become Unfaithful"), better known as „Das Treuelied“, written by the poet Max von Schenkendorf, used exactly the same melody as the "Wilhelmus".[citation needed] After World War I, this song became popular among German nationalist groups. It became one of the most popular songs of the SS, together with the „Horst-Wessel-Lied“.