How did part of Italy end up completely surrounded by Switzerland and part of Belgium sourrounded by Holland?

Question

A small part of Italy near Lugano, Switzerland and a small part of Belgium (Baarle-Nassau) just above the Belgium border and southwest of Tilburg, NL.

Answer 1

Actually, the part of Belgium there is called Baarle-Hertog; Baarle-Nassau is the Dutch city at the same general location. The division between them goes back to feudal fiefdoms in about 1198 A.D., and was preserved through many wars and border changes since then.

Campione d'Italia is an Italian enclave on the shores of beautiful Lake Como, completely surrounded by Swiss territory (part of the border line goes through the lake). This separation goes back to 1512, when Switzerland got control of Ticino, but Campione d'Italia remained the property of the Archbishop of Milan.