Carl Menger also developed a theory of the origin of money. There are no records indicating a political leader created it, and that would have been a pretty huge achievement to leave off the books. It also would have been pretty hard to convince other people to just start randomly using money.
Menger’s theory was that, when a man wanted to trade a specific illiquid good for a different good, he could have traded the illiquid good first for a good that was more liquid. He would have used the more liquid good as a stepping stone to trade for the good that he originally wanted, since, because it is more liquid, the chances went up of the man finding a trade for the good he really wanted. Because of the man’s willingness to use the more liquid good as a stepping stone, the more liquid good became even more marketable. Eventually, a good or goods became so marketable that they could be used for almost every transaction. This became money.