Complex sentence: On 10 September 1889, Albert ascended to the throne of Monaco on the death of his father and that same year in Paris on 30 October he married the Dowager Duchess de Richelieu, née Marie Alice Heine (1858-1925).
Split into simpler sentences: On 10 September, 1889, Albert ascended the throne of Monaco on the death of his father. That same year in Paris, on 30 October, he married the Dowager Duchess de Richelieu, née Marie Alice Heine (1858-1925).