Question

Why did the Ming dynasty rebuild the Great Wall of China?

Answer 1

The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally built along an east-to-west line across the historical northern borders of China to protect the Chinese states and empires against the raids and invasions of the various nomadic groups of the Eurasian Steppe. Wikipedia
@emmican

Answer 2

@emmiican

Answer 3

they rebuilt it because they needed more protection from everybody trying to kill them from japan and other states that don't like china