There are many who refer to a race as “Arcturian”; in fact there are different races that have come here from the star Arcturus. Edgar Cayce did describe one of these races accurately. In pre-Atlantean times, there were conflicts, and there were wars on the Earth. The Leonines (from Sirius) who were helped by yet another race from the constellation called Sirius, engaged in a brief war with the Reptilian races.
The starpeople from the Pleiades helped the humans learn many things; they drew (carved, or embedded using laser technology) star maps on rocks at Kariong and taught the evolving humans astronomy. They also taught them how to make fire, how to cook, and so forth. Yalarm tells there were many cities and civilisations started by different groups of starpeople on the Earth. The Atlantis that Plato wrote about is under the waters we now call the Mediterranean Sea. It was a larger evolution than many of the other places called Atlantis.
Yalarm explains that there were many races on the Earth; some came and visited, some came on the mission of the Mothership Rexegena (those on the Rexegena were from many galaxies and universes) and some were already on Earth, the reptilians, reptoids, annunaki, etc. Many built civilisations, even civilisations based on love and the human values. Due the Fall of Atlantis, much was lost, and scientists still bump up against the “missing link”. Artefacts and scientific instruments are found that could not have been created by cave-dwellers. 
Yalarm tells of the history of Earth and how the Humans were genetically engineered. Before the Fall of Atlantis, there were many races of starpeople coming and going on Earth. Electricity was generated and distributed through grids under the Earth. The grids surrounding the Earth closed up somewhat to prevent the catastrophic energy from going out and affecting other planetary systems and galaxies. This is now loosened to admit the energy from the Source of All; it will raise all life forms on Earth and bring the Golden Age. 
Those that we call “starpeople” are actually light beings existing in other dimensions. They existed in the higher dimensions we had here on Earth. With the Fall of Atlantis, the Earth peoples fell out of the 4th and 5th Dimensions. The light beings and star peoples from different races in the Universe embedded higher vibrations and light in their children by Earth peoples. This gave rise to so-called junk DNA which has come back into its own, due the return of Earth to the 4th and 5th Dimensions.