The enlightened spread all over the earth and attained many names. In the Rigveda, the highest state attainable by a human on the earth is that of a Buddha, and enlightened beings attain a body of light and eternal happiness to prove the doctrine. In other ancient texts, the awakened attain the name of Magi, Āditya, Messiah, Asura, Priest King, and so on. Ṡākyamuni Buddha was the last enlightened being to grace the earth and with passing, the Sacred Knowledge faded away. It disappeared for the whole of the Kaliyuga, the Dark Age of humanity that began about 700 BC. It was a dangerous, brutal, bloodthirsty time to be alive, and accordingly a portion of the time in Europe is called the Dark Ages. It is now over, but ignorance and danger will continue upon the earth for a long time to come. The next Golden Age is many thousands of years away, but for those interested, the knowledge to become golden is here now. The path is long but shortened by understanding, and greatly shortened by devotion and living accordingly. Here is a mantra from the Veda.
To spread the knowledge to tread the good path with good fortune and a light to investigate, with that to become an authority, and an authority is powerful with the power of love to care for others, for those to care for others and so on.