Saxe-Coburg and Gotha, or Saxe-Coburg-Gotha, was the Ernestine duchy from the House of Wettin, with the territories in the present States of Bavaria and Thuringia of Germany. It lasted from 1826 to 1918.
The name Saxe-Coburg-Gotha also refers to the family of the ruling House of Saxe-Coburg and Gotha, which played many varied roles in the dynastic and political history of Europe in the 19th and 20th centuries. At one time, in the beginning of the 20th century, before the First World War, it was the family name of the sovereigns of the United Kingdom, Belgium, Portugal, Bulgaria, and Saxe Coburg and Gotha. Today branches of the family currently reign in Belgium, the United Kingdom, and the other Commonwealth realms. The former Tsar of Bulgaria, Simeon II, kept his surname as the Prime Minister of Bulgaria from 2001 to 2005.