A divisive figure both at home and on the international arena, Mr Chavez has ruled over Venezuela since 1999.
Now aged 58, he has fought cancer since 2011 and has undergone treatment in long-time ally Cuba.
After winning presidential elections for the fourth time in 2012, Mr Chavez was due to have been sworn in during January 2013 but could not attend due to his health.
Born in the rural village of Sabaneta, Chavez is the son of two school teachers and is from modest beginnings.
His policies are widely described as socialist and anti-imperial.