Gifhorn Castle is a castle in Gifhorn, Germany, built between 1525 and 1581 in the Weser Renaissance style. The castle was fortified until 1790 with moats, ramparts and bastions and was never captured. In the 16th century it was the Residenz of the Duchy of Gifhorn under Duke Francis of Brunswick-Lüneburg for just 10 years.

The Principality of Lüneburg was a territorial division of the Duchy of Brunswick-Lüneburg within the Holy Roman Empire, immediately subordinate to the emperor. It existed from 1269 until 1705 and its territory lay within the modern-day state of Lower Saxony in Germany. The principality was named after its first capital, Lüneburg, which was ruled jointly by all Brunswick-Lüneburg lines until 1637. From 1378, the seat of the principality was in Celle. It lost its independence in 1705 when it was annexed by the Electorate of Brunswick-Lüneburg, but retained its vote in the Reichstag as Brunswick-Celle.