The UK-based Ambassador Cruise Line is expanding its fleet from 3 to 4 ships with the planned acquisition of Oceania Cruises’ 27-year-old Sirena.
The vessel, to be renamed Ambella, is scheduled to enter service with Ambassador in April 2028, operating from the German homeports of Bremerhaven and Kiel and serving the German-speaking market.
For 8 months of each year, Ambassador will charter the ship to Semester at Sea, a floating university initiative administered by the ISE/Institute for Shipboard Education. Established in 1963, Semester at Sea has 73,000+ alumni and charters ships as a platform for academic study and international travel.
The vessel has previously operated under several names and brands. Before joining Oceania as Sirena, it sailed for Renaissance Cruises as R Four, subsequently for Princess Cruises as Tahitian Princess and later Ocean Princess.
Ambella will become the first ship of Ambassador Cruise Line’s German travel brand, Ambassador Kreuzfahrten.
The company said the new brand forms part of its wider European expansion and will target German-speaking passengers while operating from German homeports.
The development follows the introduction of another international brand within the Ambassador portfolio. In September, the company announced that French operator CFC Croisières, acquired in January 2025, had been renamed Ambassador Croisières. The French operation continues to operate with French-speaking crew, with Dunkirk and Marseille serving as its ports and Renaissance as its ship.
The two developments form part of Ambassador Cruise Line’s broader strategy to establish a presence in additional European source markets. Chief Executive Officer Christian Verhounig said the German expansion was intended to support the development of a more resilient European cruise business while maintaining the characteristics on which the Ambassador operation had been built.