Alias

Juggernaut
Nick Name

Exemplar of Physical Power
Civilian ID
Cain Marko
Occupation

Criminal

Mercenary

Soldier
Legal Status
Citizen of the United States with a criminal record.
Nation or Planet of Origin
Berkeley, California
Group Affiliation

Brotherhood of Mutants

Excalibur I

Exemplars

Exiles II

Partner of Black Tom

X-Men
Base of Operations
Mobile
Height
6' 10"
Weight
900 lbs.
Eye Color
Blue
Hair Color
Red
Skin Tone
Caucasian
Known Powers
Mystical enhancement derived from the Crimson Bands of Cyttorak contained within the Ruby of Cyttorak; granting superhuman strength, endurance, durability and possibly immortality.  Able to live without nutrition, water or air for indefinite periods of time.

Limited abilities to control mystic forces by utilizing knowledge obtained while trapped within the Crimson Dimension.

Note: The Ruby of Cyttorak contains the ancient god of destruction Cyttorak, one of eight ancient gods known as the Exemplars.  Through Cain Marko's force of will, he was able to resist the transformation into Cyttorak, although he was able to harness the god's power.

The only known way to stop Juggernaut is via mental attacks, which he is shielded from by his helmet.
Accessories
Mystical Armor: Psionically shielded armor that appeared when the transformation into the Juggernaut occurred.

Ruby of Cyttorak: Ancient gem containing the essence of the ancient god of destruction, known as Cyttorak.
Common Enemies

Deadpool

Professor X

Onslaught

Spider-Man I

X-Men
Regularly Appearing

Uncanny X-Men

X-Men Vol. 2
First Appearance
X-Men Vol. 1 #12 (July, 1965)
Creator
Stan Lee & Jack Kirby
Origin
Cain Marko, the step-brother of Charles Xavier (Professor X), grew to hate his sibling, born of a frustration from his father's abuse for him and his apparent love of Xavier.  Xavier became aware of his mutant powers of telepathy, from an empathic link with his sibling, experienced during his many beatings at the hands of his father.

After the two were orphaned Xavier journeyed the world in search of adventure and other mutants, while Marko became a mercenary and became imprisoned in a third-world prison, where he met Black Tom Cassidy.

Returning to the United States, Marko enlisted in the Army and was shipped to war in South-East Asia, where the two brothers would be reunited.  Marko abandoned his post during combat and Xavier went to retrieve him.  When Xavier tracked him, Marko was hiding in the secret temple of Cyttorak.  Finding a mysterious glowing ruby gem, Marko instinctively stole it from the idol and began to transform.

At the moment of his transformation, enemy soldiers discovered the two soldiers and the temple was destroyed in an explosion.  Xavier escaped, but Marko was buried under tons of rubble.  In time he would dig his way free to menace his brother and the world as an unstoppable Juggernaut.