What did sargon ii, darius i, chandragupta maurya, and shi huangdi have in common?
they instituted state monotheism
they practiced tolerance toward conquered cultures
they promoted foreign trade
they united lands under one rule

the thing that Sargon II, darius I, Chandragupta, and Shi Huangdi have in common is : They instituted monotheism the sargon II institutiad asyrian monotheism, darius I introduced zoroastrianism as the state religion for his empire, Chandragupta Maurya instituted Jainism to his empire, and shi huangdi instituted confucianism to his empire