How can language be used to unite or divide a culture

To unite - it helps to create a normed identity through the region, and it shows the pride of that region

To divide - it can create tension with other cultures if you can't understand each other, and it can create communication problems within the culture itself

hope it helps ! :))

Unite: A language can unite the people who speak the same language through patriotisms.

Divide: A language can also divide a culture by causing tension in groups who cannot communicate with each other because they speak a different language