Taylor is charged with 11 counts of instigating murder, rape, mutilation, sexual slavery and conscripting child soldiers during the wars in Liberia and Sierra Leone in which an estimated 250,000 people died. The court is focusing on alleged crimes committed in Sierra Leone between 1996 and 2002.
Prosecutors, who closed their case in February, say Taylor directed Revolutionary United Front rebels in a campaign of terror against civilians, in the hopes of controlling neighboring Sierra Leone's diamond mines and destabilizing the government to elevate his own regional standing, according to Reuters.
The prosecution called to the stand 91 witnesses, many of whom told stories of violence, rape, amputation and even cannibalism, the New York Time reported.
When Taylor's lawyer asked him about being called a terrorist, he replied, "I am a father of 14 children, grandchildren, with love for humanity and have fought all my life to do what I thought was right. I resent that characterization of me. It is false, it is malicious."
Taylor is the first of 249 witnesses that the defense plans to call to the stand, Reuters reported. His testimony is expected to last several weeks.
His lawyer Courtenay Griffiths has said he would not contest the fact that atrocities took place but that he has no connection to them and instead was trying to broker peace in Sierra Leone.
Some of the witnesses the prosecution called were people formerly close to Taylor. These included radio operators, describing orders given from the secret communications center in Taylor's mansion, and members of the president's security force who said they witnessed the movement of arms and ammunition to the rebels and attended high-level strategy sessions, according to the New York Times.
Stephen J. Rapp, the court's chief prosecutor, said that about a dozen of these "insiders" had been moved to other countries and given new identities.
Taylor has been on trial in The Hague since June 2007 at facilities provided by the International Criminal Court.
He became Liberia's president in 1997 after a protracted civil war, stepped down in 2003 and went into exile in Nigeria, where he was arrested in 2006.
---- Compiled from wire reports and other media sources