Economy was important in the ancient world because it allowed people to gain and give. An example is shown in the image, a farmer is harvesting crops that he will sell and trade to increase in wealth.
Geography was important in the ancient world because it affected how the civilization developed. The image represents life in the Sahara. What is not shown is that citizens that lived further from the river used irrigation systems for farming and other uses.
Leadership and government were important in the ancient world because they kept people and things together. To go further into dept, social classes ( as shown in the image above) allowed certain jobs to be done and money levels to be controlled. Leadership keeps people unified, inputs rules, and helps them live a certain way.