Complex sentence: Princess Marie of Saxe-Weimar-Eisenach (3 February 1808 in Weimar--18 January 1877 in Berlin), was a princess of Saxe-Wiemar-Eisenach by birth, and by marriage a princess of Prussia.
Split into simpler sentences: Princess Marie of Saxe-Weimar-Eisenach was born on 3 February 1808 in Weimar. She was a princess of Saxe-Wiemar-Eisenach by birth, and by marriage a princess of Prussia.