Daniel 5:29 - "Then Belshazzar commanded, and Daniel was clothed with purple, a chain of gold was put about his neck, and proclamation was made concerning him, that he should be the third ruler in the kingdom."

The ruler, as I’m sure you’re saying to yourself, is rather obviously someone who rules or governs, or who assists in carrying on a government. Although we associate this position primarily with inheritance, as in the case of England’s ruler, Queen Elizabeth, in the ancient world, this title was often bestowed by kings on their subjects as a signal act of honor. For example, Daniel was made ruler over the whole province of Babylon by Nebuchanezzar for interpreting a dream, and again made third ruler of the kingdom after interpreting the writing on the wall at the time of Belshazzar’s great feast.

There were also, in later times, the ruler of the synagogue; the ruler of the treasure, or the chief treasurer; and the high priest, who was considered the "ruler of the house of God."

We have already made the obvious comparison. In our laregly democratic world today, the inherited ruling positions are fading away, and we no longer consider them as highly influential persons. But, at one time, the ruler held the power of life and death over his subjects, and everything that that implies went with this power.