Buise was one of the East Frisian Islands off the North Sea coast of Germany that was almost entirely engulfed by the sea in the second half of the 17th century. The only remaining part is the eastern end, known today as the island of Norderney. Buise itself was formed by the breakup of a bigger island. Two possible origins are mentioned: the breakup of the island in the flood of 1219, and the breakup of the island in 1170, which also formed Juist, Borkum and Memmert.