A King Sat on the Rocky Brow (Summit)

In this poem by Lord Byron, the poet re-imagines the ancient battle of Salamis, in which Xerxes, king of Persia was defeated by a Greek coalition in 480 B.C. The poem highlights how quickly the fortunes of nations can change in an instant:

A king sat on the rocky brow (summit)
Which looks o’er sea-born Salamis
And ships, by thousands, lay below,
And men in nations; –all were his!
He counted them at break of day–
And when the sun set where were they?