Taylor, the first African head of state to be tried by an international court, has pleaded not guilty to 11 charges including murder, torture, rape, sexual slavery, using child soldiers and spreading terror.
Prosecutors at the U.N.-backed Special Court for Sierra Leone have called 91 witnesses since January 2007. Now it is Taylor's turn.
The former Liberian president's lawyer has urged judges at the Special Court for Sierra Leone not to let the horrors inflicted by rebels during the country's civil war cloud their judgment about Taylor's involvement in the crimes.
"His case is that he was not involved," Taylor's British lawyer Courtenay Griffiths told The Associated Press in a telephone interview. "That he was a peacemaker, not a warmonger."
Griffiths will deliver his opening statement Monday and the former president will take the stand Tuesday for what is expected to be weeks of testimony in his own defense.
Taylor was forced into exile after being indicted in 2003 and was finally arrested in Nigeria three years later. He was sent for trial in The Hague in June 2006 because officials feared staging the case in Sierra Leone could spark further violence.
He boycotted the start of his trial in June 2007 and fired his attorney, holding up proceedings until January 2008 when prosecutors called their first witness.
Witnesses testified about radio exchanges between Taylor and the rebels, arms smuggled from Liberia to Sierra Leone in sacks of rice and diamonds sent back in a mayonnaise jar. One former aide said he saw Taylor eat a human liver.
"We say and have said all along that they are lying," Griffiths said of the prosecution witnesses.
It is estimated that about a 500,000 people were victims of killings, systematic mutilation and other atrocities in Sierra Leone's 1991-2002 civil war. Some of the worst crimes were carried out by gangs of child soldiers fed drugs to desensitize them to the horror of their actions.
After Taylor, the defense team has a list of more than 200 witnesses, though not all are expected to testify. Among them are former African heads of state and high-ranking U.N. officials who will testify on his behalf, according to a list that does not name them.
Griffiths aims to portray Taylor as a peace maker asked by the 15-member Economic Community of West African States and the United Nations to help halt the atrocities in Sierra Leone.
Dan Saryee, a rights advocate who runs the pro-democracy Liberia Democratic Institute, dismissed the idea.
"Taylor's war machinery was never a peacekeeping force; how could it go into Sierra Leone to make peace?" Saryee said. "It is unthinkable."