Krum the Fearsome (, ) was
Khan of
Bulgaria during the
First Bulgarian Empire from sometime after 796 but before 803 until his death in 814. During his reign the Bulgarian territory doubled in size, spreading from the middle
Danube to the
Dnieper and from
Odrin to the
Tatra Mountains. His able and energetic rule brought law and order to Bulgaria and developed the rudiments of state organisation.