Sitmar Cruises and its predecessor Sitmar Line were company names derived from the acronym for the Società Italiana Trasporti Marittimi. SITMAR originally was an Italian shipping line founded by Russian émigré Alexandre Vlasov, however the company's headquarters were later transferred to Monaco. Vlasov initially operated cargo services from 1937, gradually replacing these with passenger services from 1947 until 1988, when SITMAR was sold to the Peninsular and Oriental Steam Navigation Company (P&O). After the sale, most of the former SITMAR ships were transferred to the fleet of P&O subsidiary Princess Cruises, while one, TSS Fairstar, became the sole vessel of the newly created P&O-Sitmar Cruises. The only ship originally ordered by SITMAR still sailing, is the MS Ambience for Ambassador Cruise Line.

Princess Cruises is an American cruise line owned by Carnival Corporation & plc. The company is incorporated in Bermuda and its headquarters are in Santa Clarita, California. As of 2021, it is the second largest cruise line by net revenue. It was previously a subsidiary of P&O Princess Cruises. The line has 15 ships cruising global itineraries that are marketed to both American and international passengers.