A second crisis emerged due to a succession dispute. The Dukedoms of Schleswig and Holstein were legally inherited under Salic law which ignored females; the Kingdom of Denmark had a different inheritance law which permitted male heirs to inherit through the female line. Under these varying succession laws, the childless King Frederick VII of Denmark would have different heirs in Denmark and in Schleswig-Holstein. But when Frederick died in 1863, his Danish heir Christian IX claimed to have inherited the Duchies as well, and attempted to reintegrate the Duchy of Schleswig into the Danish kingdom by the signing the so-called November Constitution. This was seen as a violation of the London Protocol, and it led to the Second Schleswig War of 1864 and ultimately to the Duchies' absorption into Germany.