Chandragupta's grandson, the famous Açoka, not only maintained his national Indian empire, but extended it in every direction. Having adopted Buddhism as the state religion, he did much to spread its doctrines, especially to Ceylon, which since then has remained the most faithful guardian of Buddhist tradition.
After Açoka's death the Græco-Bactrian princes began about 200 B.C. to conquer Western India, and ruled there for about eighty years. Euthydemos extended his dominions to the Jhelum. His son Demetrios (early in the second century B.C.) appears to have held sway over the Lower Indus, Mālava, Gujarat, and probably also Kashmir. He is called "King of the Indians," and was the first to introduce a bilingual coinage by adding an Indian inscription in Kharoshṭhī characters on the reverse to the Greek on the obverse. Eukratides (190-160 B.C.), who rebelled against Demetrios, subjected the Panjāb as far east as the Beäs. After the reign of Heliokles (160-120 B.C.), the Greek princes in India ceased to be connected with Bactria. The most prominent among these Græco-Indians was Menander (c. 150 B.C.), who, under the name of Milinda, is well known in Buddhist writings. The last vestige of Greek domination in India disappeared about 20 B.C., having lasted nearly two centuries. It is a remarkable fact that no Greek monumental inscriptions have ever been found in India.
With the beginning of the Græco-Indian period also commenced the incursions of the Scythic tribes, who are called Indo-Scythians by the Greeks, and by the Indians Çakas, the Persian designation of Scythians in general. Of these so-called Scythians the Jāts of the Panjāb are supposed to be the descendants. The rule of these Çaka kings, the earliest of whom is Maues or Moa (c. 120 B.C.),