The Duchy of Holstein-Gottorp was a historical territory located in northern Germany. It emerged in the 16th century when the Duke of Holstein inherited the Duchy of Gottorp, creating a union of the two regions. The duchy was part of the larger Duchy of Holstein, which was under the influence of the Danish Crown. Holstein-Gottorp played a significant role in European politics, particularly during the Northern Wars and the Great Northern War. The duchy was eventually absorbed into the Danish Realm in the 18th century, leading to its dissolution as a separate entity.