Image credits

All portraits are Public domain on Wikimedia Commons (AttributionRequired = false). Cropped locally for the site.

Napoleon: Jean-Auguste-Dominique Ingres, Napoleon I on his Imperial Throne (1806).
File: Ingres,_Napoleon_on_his_Imperial_throne.jpg — Public domain.
Cleopatra: Posthumous painted portrait of Cleopatra VII of Egypt, from Herculaneum, Italy.
File: Posthumous_painted_portrait_of_Cleopatra_VII_of_Egypt,_from_Herculaneum,_Italy.jpg — Public domain (PD-Art).
Alexander: Detail from the Alexander Mosaic (Battle of Issus), House of the Faun, Pompeii.
File: Alexander_(Battle_of_Issus)_Mosaic.jpg — Public domain. (Avoided Getty-sourced mosaic variants.)
Shakespeare: Chandos portrait of William Shakespeare (National Portrait Gallery).
File: Shakespeare.jpg — Public domain (PD-Art).