It is rare that, in human history, a specific sexual position is given any sort of inventor. Most of them probably predate humanity as we think of it. The majority of the rest are simple enough that cultures independently invent them before they meet each other. There are stories of cultures transmitting certain ideas. For instance, it was said that the Greeks had taught the Persians about the possibility of anal sex, but even then, there is no original Greek inventor of the concept.
The single exception of which I know is the “daisy chain.” This term has several variations, all of which involve a circle of people performing the same action on the next person that is being performed on them by the previous person in the circle. However, the specific variation to which I refer is that in which a circle of men each anally penetrate the man in front of them.
According to history, the daisy chain was invented by the Roman emperor Tiberius, during his long retreat on the island of Capri. A great deal of sexual improprieties were attributed to him, though, so perhaps this should be taken with a grain of salt. Nevertheless, it makes the position unique in the annals of history to the best of my knowledge.