Cause and effect plays a major role in determining how people respond to their environments. What has caused an obstacle to exist? What specific effects does it have on the person's life? What effects will certain reactions have down the road? The answers to all of these questions depend on the historical context.
Think of your favorite movie. If you were to change the time to be 200 years in the past (or 200 years in the future), what might change about the story? If you were to move the location 2,000 miles away, what else might change?
Think of this class. If you were taking it 30 years ago, what might be different? If you were taking it in another country, what else might be different?