Wilhelm II, also known as Willy to his royal relatives, was the Kaiser of Germany during World War I.
"Willy" was the cousin of Edward VII. In 1902, King Edward believed that his cousin would have jumped at Professor Challoner's offer to rule the world. (PROSE: Revenge of the Judoon)
In 1903, after receiving a wealth of information from the future, Grigori Rasputin foresaw the Kaiser's role in the First World War. (AUDIO: The Wanderer)
After the Eighth Doctor told Molly O'Sullivan about the Daleks' aggressive nature, she compared them to the Kaiser. (AUDIO: Fugitives)