He was a preacher, president, and warlord. Charles Taylor was a warlord before he became president of Liberia. In 1989 when his National Patriotic Front of Liberia (NPFL), alliance with Prince Johnson, another rebel leader, overthrew the presidency of Samuel K. Doe and took power. He then tried to intervene in neighboring Sierra Leone, using his NPFL forces together with RUF soldiers, and tried to overthrow the government of Jospeh Momoh. A gruesome civil war ensued.
When he was elected president of Liberia in 1997, he used his political power and status to fund RUF soldiers across Sierra Leone. He quietly provided weapons, ammunition, shelter and medical supplies that helped drive a viscous campaign of rape, torture, murder and mutilation that resulted in the death of over 50,000 people, and the mutilation of thousands more. His doings also supported the use of child soldiers in Sierra Leone. He encouraged the recruitment and brainwashing of innocent children to turn them into cold blooded killers that will fight for the RUF.
He helped plan with the RUF commander Sam Bockaire, attacks on the towns of Kono, Makeni and Freetown that took place in late 1998 and early 1999.
He stepped down from the presidency amid accusations of war crimes, and disappeared. He was later found, arrested and tried in the first ever war crimes trial since the Nuremberg trials of the Nazis. He was found guilty on 11 counts of war crimes, crimes against humanity and violations of international humanitarian law.
Acts of Terrorism
Violence to life, health, physical or mental well beings of person, murder in particular
Outrages upon personal dignity
Other inhumane acts
Use of child soldiers
At the already late age of 63, he was sentenced to 50 years in prison in May of 2012. He is currently serving his sentence in a UK prison.
Most useful source: https://www.opensocietyfoundations.org/briefing-papers/trial-charles-taylor-special-court-sierra-leone-appeal-judgment