Boris Godunov became tzar when Feodor, Ivan The Terrible's son died in 1598. Feodor was too young to have any heirs and his younger brother, Dmitri had died mysteriously. Since Boris had been Feodor's regent he was elected by the Imperial Embasy to the throne. Later in Boris's reign many would claim to be Dmitri in order to take the throne, but Boris had them killed. Many believed that Boris had the original Dmitri killed in order to inherit the throne.