It happened in 1993 when an inscription in Bactrian and Greek was found in a place called Rabatak between Kabul and Mazar-i-Sharif when the Mujahideen were digging a trench along with many cultural treasures. It gave a complete account of the genealogy of the early Kushan Empire and some details till the reign of Kanishka, one of the most powerful and one of the most enigmatic empires in the cross roads between India, China and Persia. It is assumed that the Kushans are a part of the Xiongnu federation residing on the North Western borders of China and enjoying a love-hate relationship with the Chinese all their career. May be due to the Chinese pressure, they were slowly pushed towards India and as time passed on, became Indianized. They were seriously damaged due to an invasion of the Sassanians and were replaced by some remnants under the name Kushahshahs/Indo-Sassanians.

The inscription goes thus –

“The year one of Kanishka, the great deliverer, the righteous, the just, the autocrat, the god, worthy of worship, who has obtained the kingship from Nana and from all the gods, who has laid down (i.e. established) the year one as the gods pleased.”
“And it was he who laid out the Ionian speech and then placed the Arya  speech (i.e. replaced the use of Greek by the Aryan language).”
“In the year one, it has been proclaimed unto India, unto the whole realm of the governing class including Koonadeano (Kaundinya) and the city of Ozeno (Ujjain) and the city of Zageda (Saketa) and the city of Kozambo (Kausambi) and the city of Palabotro (Pataliputra) and so long unto the city of Ziri-tambo (Sri-Champa).”
“Whichever rulers and the great householders there might have been, they submitted to the will of the king and all India submitted to the will of the king.”
“The king Kanishka commanded Shapara, the master of the city, to make the Nana Sanctuary, which is called (i.e. known for having the availability of) external water (or water on the exterior or surface of the ground), in the plain of Kaeypa, for these deities – of whom are Ziri (Sri) Pharo (Farrah) and Omma.”
“To lead are the Lady Nana and the Lady Omma, Ahura Mazda, Mazdooana, Srosharda, who is called … and Komaro (Kumara)and called Maaseno (Mahasena) and called Bizago (Visakha), Narasao and Miro (Mihara).”
“And he gave same (or likewise) order to make images of these deities who have been written above.”
“And he ordered to make images and likenesses of these kings: for king Kujula Kadphises, for the great grandfather, and for this grandfather Saddashkana (Sadashkana), the Soma sacrificer, and for king V’ima Kadphises, for the father, and for himself, king Kanishka.”
“Then, as the king of kings, the son of god, had commanded to do, Shaphara, the master of the city, made this sanctuary.”
“Then, the master of the city, Shapara, and Nokonzoka led worship according to the royal command.”
“These gods who are written here, then may ensure for the king of kings, Kanishka, the Kushana, for remaining for eternal time healthy., secure and victorious… and further ensure for the son of god also having authority over the whole of India from the year one to the year thousand and thousand.”
“Until the sanctuary was founded in the year one, to then the Great Arya year had been the fashion.”
“…According to the royal command, Abimo, who is dear to the emperor, gave capital to Pophisho.”
“…The great king gave (i.e. offered worship) to the deities.”