Free lance has its origins in Germany. It was a military concept of being a free land trooper, meaning that a soldier sold his military service to the highest bidder. (There were other reasons for service but money was usually the prime motivator.) During the second half of the Middle Ages, free lance soldiers were prevalent in Europe, especially in Italy and France. Mercenary, a term that brings us images of pirates, is another name for these free lancers. Soldier of fortune is another.
Later, politicians who did not affiliate with any particular party were known as freelancers. Today, the term is most commonly used to refer to the writing profession. A journalist who writes for a variety of news sites and magazines, without formal employment is called a freelancer.
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