Origin

The Federation call the Iotion planet Sigma Iotia II.  The Iotian planet was heavily influenced by Humans before the Prime Directive when the Ship U.S.S. Horizon visited the planet.  It was so badly influenced that when the Federation Starship U.S.S. Enterprise arrived at the planet decades later more than half the planet had adopted a Human culture.  The culture was based on Chicago Mobs of the 1920's.  
 
Captain James Kirk of the Enterprise convinced the mobs of the planet that the Federation was the biggest mob of the world and that he was taking over and would allow them to get a piece of the action.  This would allow him to escape with his crew and give the Federation time to figure out what to do next to fix the contamination problem.   Leonard McCoy however left his communicator on the planets surface and this may change the Iotian culture again.  

Creation

The Iotians were created during the original Star Trek television show.