William III, Prince of Orange
William III, the Dutch king of the time is personified through the entire nation. Dryden refers to the Dutch, meaning specifically William. He is the one who instructs his navy to continue to threaten Britain for the sake of naval superiority during the Anglo-Dutch War.
Charles II
Charles is the King of England during 1666. He is the one who builds the navy's supremacy as a global superpower because he wants to establish his empire's dominance. Charles is a proud king, however, and refuses to allow his country to recover after the war. He picks fights continually with neighboring countries, which decreases his popularity among his subjects dramatically. When tragedy strikes in the form of the plague, he is next to useless. He does, however, regain popularity when his decree saves the city of London from complete obliteration during the great fire.
Louis XIV
He was the King of France. Louis is to whom Dryden refers when he speaks of France. His aid in the Anglo-Dutch war is accredited with the English victory. Unable to be bothered with true aid to England, he proves an unstable ally who needs constant watching.
Death
Dryden personifies Death in the poem. He isn't someone to be feared; he's a familiar and almost welcome friend to the people. 1666 was a year filled with so much death, that the people ceased to shutter when he knocked on their doors.
God
As Christianity was the prominent religion of the time, Dryden focuses on God several times in his poem. God is credited with creating all life. It is then His divine right to end life when He sees fit, and the people do not question it. God's character is not really typified as either good or bad but merely expressed through his actions. In any situation, God is given praise eventually as His ways are considered mysterious and just in any circumstance, even when the people cannot understand His actions.