MS Sobieski was a Polish passenger ship built for the Polish Ocean Lines to replace the aging SS Kościuszko and SS Pulaski; a sister ship to the MS Chrobry. She was named in honour of the Polish king Jan III Sobieski.The ship was used as a troopship in the Allied evacuation of western France in 1940 (Operation Ariel), the Battle of Dakar and the campaign in Madagascar.