The command human was an Illusion spell. It first appeared along with the other Command spells sometime during the founding of the Mages Guild. It became popular throughout all of Tamriel and especially throughout the teenagers. But at the first days of the Third Era its skill was in doubt. The Archmages and the top ranked mages became fearful of the spell's effects. And they were right. The spell's ability to control not only a human but generally a sentient, led to a series of bloody conflicts which eventually fragmented the Empire. Then the Mages Guild abolished its practicing, and ordered the execution of anyone alive who practices it. Thousands were in jail, and thousands were executed. In the end the spell was forgotten. Tiberius Stormrider however one day came to experience the spell and to learn it. Ria Silmane, Tiberius's mentor warned him that the spell's further use could be very dangerous.
During the dawn of the Second Era, when the Mages Guild was founded, philosophers tried to create a spell which would command mortal minds and make the victim the slave of the caster. It was however not for evil use.