Among the most remarkable illuminated manuscripts to survive from the fourteenth century is a copy of the Semideus or Demigod, a tract on military matters by the humanist Catone Sacco. It's one of the works featured in Meetings with Remarkable Manuscripts by Christopher de Hamel. Sacco presented this copy to Duke Filippo Maria Visconti of Milan in 1438. That's the duke above, watched over by the Virgin.
The text is half military history, half flattery of the "Semideus," that is, the Demigod, who of course in the Duke himself. The point seems to have been to convince the Duke to go on crusade and save Constantinople from the Turkish hordes.
The charming illustrations show historical battles, half taken from ancient authors and the rest from chronicles of the crusades. That's our old friend the ship casting post full of snakes at its enemies, a story which Sacco of course accepted without reservation, as any good humanist would.
Interesting way to batter down a fortress. Leonardo wasn't the only Renaissance Italian hatching wild military schemes.
I find these paintings delightful and original. I've never seen anything else quite like them, and they form a great picture of how a humanist scholar imagined the world of war.