'Jihad is being paid for by Europe', says Al Qaeda leaders," from the BBC, 13 December 2013
"Barbary corsairs led attacks upon American merchant shipping in an attempt to extort ransom for the lives of captured sailors, and ultimately tribute from the United States to avoid further attacks, much like their standard operating procedure with the various European states.
In agreeing to pay a ransom of $60,000 for the American prisoners, the Jefferson administration drew a distinction between paying tribute and paying ransom. 1805
Source: wikipedia: First Barbary War.