Complex sentence: Having been caught before he reached the palace, he was sent back to his ship, and he was last mentioned in the newspapers in 1844, when he was rescued after going overboard between Tunis and Algiers.
Split into simpler sentences: Having been caught before he reached the palace, he was sent back to his ship. He was last mentioned in the newspapers in 1844, when he was rescued after going overboard between Tunis and Algiers.