Already, in the interval between the conclusion of the general truce and of the fifty years' peace, he had, as it seems, invaded the territories of the Ephthalites, and, with the help of the Great Khan of the Turks, inflicted upon this people, so long one of Persia's most formidable enemies, a severe defeat.

According to Tabari, he actually slew the Ephthalite monarch, ravaged his territory, and pillaged his treasures.
About the same time he had also had a war with the Khazars, had overrun their country, wasted it with fire and sword, and massacred thousands of the inhabitants.

He now entertained designs against Arabia and perhaps India, countries on which he could not hope to make an impression without earnest and concentrated effort.

It was doubtless with the view of extending his influence into these quarters that the Persian monarch evacuated Lazica, and bound his country to maintain peace with Rome for the next half-century.
The position of affairs in Arabia was at the time abnormal and interesting.

For the most part that vast but sterile region has been the home of almost countless tribes, living independently of one another, each under its own sheikh or chief, in wild and unrestrained freedom.
Native princes have seldom obtained any widely extended dominion over the scattered population; and foreign powers have still more rarely exercised authority for any considerable period over the freedom-loving descendants of Ishmael.