SMS König Wilhelm (King William) was an armored frigate of the Prussian and later the German Imperial Navy. The ship was laid down in 1865 at the Thames Ironworks shipyard in London, originally under the name Fatikh for the Ottoman Empire. She was purchased by Prussia in February 1867, launched in April 1868, and commissioned into the Prussian Navy in February 1869. The ship was the fifth ironclad ordered by the Prussian Navy, after Arminius, Prinz Adalbert, Friedrich Carl, and Kronprinz. She was built as an armored frigate, armed with a main battery of sixteen and five guns; several smaller guns and torpedo tubes were added later in her career.