Schleswig-Holstein is the northernmost of the 16 states of Germany, comprising most of the historical Duchy of Holstein and the southern part of the former Duchy of Schleswig. Its capital city is Kiel; other notable cities are Lübeck and Flensburg.
Historically, the name can also refer to a larger region, containing both present-day Schleswig-Holstein and the former South Jutland County in Denmark. It covers an area of 15,763 km2, making it the 5th smallest German federal state by area.
Schleswig was under Danish control during the Viking Age, but in the 12th century it escaped full control and became a duchy. It bordered Holstein, which was a part of the Holy Roman Empire.
Wikipedia https://en.wikipedia.org/wiki/Schleswig-Holstein
Coordinates 54°19'21.751" N 10°8'7.998" E