The Kushan Empire originally forms in the early 1st century CE under Kujula Kadphises in the territories of ancient Bactria on either side of the middle course of the Oxus (or Amu Darya), and is later based in eastern and northern Afghanistan and the north-west of the Indian Subcontinent.During the 1st and early 2nd centuries CE the Kushans expand rapidly across the northern part of the Indian Subcontinent at least as far as Saketa and Sarnath near Varanasi (Benares) where inscriptions have been found dated to the first few years of the era of the most famous Kushan ruler, Kanishka which apparently began about 127 CE.

The Kushan were a branch of the Yuezhi confederation.

Previously a nomadic people residing in eastern Central Asia, the Yuezhi move southwest and settle in ancient Bactria.

They have diplomatic contacts with the Roman Empire, Sassanid Persia and Han China.

While much philosophy, art, and science is created within its borders, the only textual record we have of the empire's history today comes from inscriptions and accounts in other languages, particularly Chinese.

The empire declines from the 3rd century and falls to the Sassanid and Gupta Empires.