Bygone leaders is a term used to refer to the rulers of past empires and dynasties. Tsars, Kaisers, Shahs, and CZARS are all examples of bygone leaders. Tsars were the rulers of Russia from the 16th century until the Russian Revolution in 1917. Kaisers were the rulers of Germany from 1871 to 1918. Shahs were the rulers of Iran from 1501 to 1979. CZARS were the rulers of Russia from the 10th century until the Russian Revolution in 1917.