Regardless of time or place, governments have always needed sources of revenue. Most commonly, government revenue came from taxes on agricultural production, manufacturing, or customs duties on trade. Usually an individual or bureaucracies of people were made tax collectors to gather the goods and moneys owed to the government. Efficient and trustworthy tax collectors helped keep the rate of taxes low. Inefficient or corrupt tax collectors increased the tax burden, leading to civil unrest and injustice.