The empire was founded in the aftermath of three wars by the North German state of Prussia. Otto von Bismarck, the prime minister of Prussia (and later the first chancellor of the Empire) led diplomatic discussions with the rulers of the North German Federation states of Bavaria, Baden, Hesse-Darmstadt, and Württemberg regarding unification. An agreement was struck and on January 18th the German Empire was officially established. It was dissolved after Germany’s defeat in WWI.
Other notable events on January 18th:

In 2002, the civil war in Sierra Leone, which killed more than 50,000 and displaced 2,000,000 people, is officially declared over.

In 1919, with the objective of setting the peace terms in the aftermath of WWI the Paris Peace Conference begins, which resulted in the signing of the Treaty of Versailles.

In 1912, British explorer Robert Falcon Scott and his team reached the South Pole, only to discover that explorer Roald Amundsen had beat them to it by a month. All men died on their return journey.

In 1886, the Hockey Association in England formalized the modern version of hockey.

Otto von Bismarck, first Chancellor of the German Empire/ Library of Congress