Complex sentence: Surcouf had an altercation with Decaen but had to renounce his ship, and eventually purchased the "Sémillante", which he renamed "Charles", to return to France.
Split into simpler sentences: Surcouf had an altercation with Decaen but had to renounce his ship. Surcouf eventually purchased the "Sémillante", which he renamed "Charles", to return to France.