Complex sentence: With the establishment of the German Empire in 1871, Holstein became secretary of the ambassador in Paris, Harry von Arnim, a patroniser of the French royalists and a fierce opponent of Chancellor Bismarck, who finally enforced Arnim's discharge and conviction for breach of secrecy.
Split into simpler sentences: With the establishment of the German Empire in 1871, Holstein became secretary of the ambassador in Paris, Harry von Arnim. Von Arnim was a patroniser of the French royalists and a fierce opponent of Chancellor Bismarck, who finally enforced Arnim's discharge and conviction for breach of secrecy.