“History is philosophy teaching by examples.”
Thucydides, The History of the Peloponnesian War
The History of the Peloponnesian War* in three volumes, translated by S. T. Bloomfield, annotated from the best commentators and historians, and prefixed with the Life of Thucydides by the same author:
Volume I, Volume II, Volume III.
* The pictured quote was attributed to Thucydides in the 3rd century AD but does not appear in The History of the Peloponnesian War; it was perhaps found in other writings of his which have since been lost.