Complex sentence: Magdalena Sibylla of Hesse-Darmstadt (28 April 1652--11 August 1712) was regent of the Duchy of Württemberg from 1677 to 1693, and was a prominent German composer of baroque hymns.
Split into simpler sentences: Magdalena Sibylla of Hesse-Darmstadt (28 April 1652--11 August 1712) took over from 1677 to 1693 the regency of the Duchy of Württemberg. She was a prominent German composer of baroque hymns.