Agnes Bernauer, a play in German

According to Wikipedia: "Christian Friedrich Hebbel (March 18, 1813 – December 13, 1863), was a German poet and dramatist… In 1840 he wrote the tragedy Genoveva, and the following year finished a comedy, Der Diamant, which he had begun at Munich. In 1842 he visited Copenhagen, where he obtained from King Christian VIII a small travelling studentship, which enabled him to spend some time in Paris and two years (1844-1846) in Italy. In Paris he wrote his fine "tragedy of common life," Maria Magdalene (1844). On his return from Italy Hebbel met at Vienna two Polish noblemen, the brothers Zerboni di Sposetti, who in their enthusiasm for his genius urged him to remain, and supplied him with the means to mingle in the best intellectual society of the Austrian capital..."