The "Tsar of Bulgaria" refers to the monarch who ruled over the Kingdom of Bulgaria from its establishment in the late 7th century until the abolition of the monarchy in 1946. The title "Tsar" is derived from the Latin word "Caesar," signifying a ruler of high authority. Notable Tsars include Boris I, who converted Bulgaria to Christianity, and Simeon I, known for expanding the kingdom and fostering a cultural renaissance. The Bulgarian monarchy played a significant role in the country's history, influencing its political, cultural, and religious development. The last Tsar, Simeon II, ascended to the throne as a child in 1943 but was deposed in 1946 when Bulgaria became a republic. The legacy of the Tsars remains an important part of Bulgaria's national identity.