Datis fell back upon Asia, having suffered worse disasters than his predecessor, and bore to the king the melancholy tidings that his vast force of from 100,000 to 200,000 men had been met and worsted by 20,000 Athenians and Plataeans.
Still Darius was not shaken in his resolution.

He only issued fresh orders for the collection of men, ships, and materials.

For three years Asia resounded with the din of preparation; and it is probable that in the fourth year a fresh expedition would have been led into Greece, had not an important occurrence prevented it.

Egypt, always discontented with its subject position under a race which despised its religion, and perhaps occasionally persecuted it, broke out into open revolt (B.C.
487).

Darius, it seems, determined to divide his forces, and proceed simultaneously against both enemies; he even contemplated leading one of the two expeditions in person; but before his preparations were completed his vital powers failed.