Page "Battle of Marathon" Paragraph 2

The defeat at Marathon marked the end of the first Persian invasion of Greece, and the Persian force retreated to Asia.

Darius then began raising a huge new army with which he meant to completely subjugate Greece ; however, in 486 BC, his Egyptian subjects revolted, indefinitely postponing any Greek expedition.

After Darius died, his son Xerxes I restarted the preparations for a second invasion of Greece, which finally began in 480 BC.