Complex sentence: Hun has a history of several different settlements, each being built to replace an earlier village swallowed up by the desert, which explains why it is called "El-Huwailah" the migrating town.
Split into simpler sentences: Hun has a history of several different settlements, each being built to replace an earlier village swallowed up by the desert. Which explains why it is called "El-Huwailah" the migrating town.