The term 'OLD RULER OF RUSSIA' can be summarized by the crossword solution 'TSAR', which is a four-letter word. TSAR was the title of the monarchs of Russia from 1547 to 1917, when the monarchy was abolished and replaced with the Soviet Union. Tsars were absolute rulers who had complete control over their subjects and the government. They were often seen as divinely appointed rulers, and their power was absolute.