Ivar the Boneless was a fearsome 9th-century Viking leader, son of Ragnar Lothbrok, renowned as a brilliant strategist and ruthless commander of the Great Heathen Army, despite a mysterious physical disability suggested by his nickname, which might stem from brittle bone disease (Osteogenesis Imperfecta), extreme flexibility, or even impotence, rather than being literally legless. He was cunning, strategic, and led devastating invasions in England, becoming a legendary figure known for both terror and tactical genius, often depicted carried on a shield.

Physical & Personality Traits:
The "Boneless" Nickname: Theories suggest hypermobility, brittle bones (Osteogenesis Imperfecta), or even a Latin mistranslation ("exosus" meaning "detestable").
Strategic Genius: A master tactician, he used cunning, like the oxhide trick to claim land, making him a feared and respected leader.
Ruthless & Cunning: Known for brutality and a ruthless personality, seeking power and proving himself.
Physically Disabled: Sagas describe him as needing to be carried on a shield, highlighting his physical limitations.

Historical Significance:
Leader of Great Heathen Army: Led the invasion of England in 865 AD, causing immense destruction.
Fall of Kings: Responsible for the demise of several Anglo-Saxon kings, including Ælla.
Norse Dynasty: Linked to Ímar, founder of a powerful dynasty in Dublin, Ireland.

Portrayal: Sagas & History: Depicted as a large, strong, yet disabled figure, sometimes as a berserker.