SMS Seeadler ("Sea Eagle") was a successful commerce-raiding warship of the Imperial German Navy during World War 1 (1914-1918). Originally, the vessel was an American merchant named Pass of Balmaha in reference to the Scottish village of Balmaha. She was ordered in 1888 and constructed by R. Duncan & Company in Port Glasgow, Scotland to which then she entered into commercial service flying the American flag - she remained in this role until 1915.
Her design incorporated three sailing masts and she was categorized as a "windjammer", a sail-powered ship built with a steel or iron hull. Her crew complement numbered 64 and she carried no guns for the role. Dimensions included a length of 83.5 meters, a beam of 11.8 meters and a height of 5.5 meters.
In the summer of 1914, war in Europe had broken out. While the United States remained neutral until 1917, it still had to navigate waters teeming with all sorts of trouble. The vessel was stopped by the British Navy en route to the Russian port city of Archangelsk carrying supplies for the Russian war effort against Germany (along the East Front). The British forced the American ship to reroute to Kirkwall, northern England, for a complete inspection and even stationed an enforcement crew aboard Pass of Balmaha as insurance. Now sailing under the British flag, she was eventually corralled by the German U-Boat U-36 and forced o Cuxhaven where she was given a complete inspection by the enemy - her crew was released but the ship fell to the Germans.
Pass of Balmaha was reborn as SMS Seeadler when commissioned in 1915 and figured into the role of commerce raider for the Germans. Some modifications to her design were enacted such as the introduction of 2 x 105mm guns, machine guns for local defense, and reworked internal space for crew and prisoner holds. To complement her inherent sailing power, an auxiliary diesel engine of 900 horsepower was installed.
SMS Seeadler made it beyond the British blockade under the guise of being a Norwegian sailing vessel in late 1916. This gave her complete access to the Atlantic Ocean once she cleared danger. From then on she amassed a considerable career as a successful commerce raider for the German Imperial Navy - capturing or sinking some sixteen total enemy ships (about 30,100 tons worth).
Her luck ran out in August of 1917 when she struck a reef near Tahiti of French Polynesia. She went on to capture one more enemy vessel - a French schooner in September before she was purposely grounded at Easter Island. The crew was then collected by the Chilean government and interned, bringing about an end to her reign of the high seas.