Ivan IV the Terrible crowned himself first Tsar of Russia in 1547 at the age of 17.
The first Tsar of Russia had a troubled childhood. His father died just after he turned three. He lost his mother five years later. As an eight-year-old was too young to rule, the royalty started warring for power. Some historians think this environment as Ivan grew shaped him into a ruthless leader. Finally, at the age of 17, Ivan took the throne and started a time of change.
For about 13 years Ivan made many changes. He centralized the government and culture. He fought and won a few wars. Unfortunately after 1560, it all changed. He started a long war that ended in disaster for Russia, then began his reign of terror.
For a couple of decades, Ivan created his own police force. He had them attack and put down anyone that dissented against him. He used them to seize private land and terrorized the people, especially royalty. This time period almost eradicated any good he had done previously. Finally, he died in 1584, leaving his country in almost ruins. It took almost a century for Russia to emerge from the chaos created in his final years.