William Edward Hartpole Lecky 
History of European Morals: From Augustus to Charlemagne. Volume I 

This 2 part book, originally published in 1890, was written to help students of morals comprehend the significance of morals. The questions with which an historian of morals is chiefly concerned are the changes that have taken place in the moral standard and in the moral type, the degrees in which, in different ages, recognised virtues have been enjoined and practiced and the relative importance that in different ages has been attached to different virtues.