It's very popular to find non-business related topics and turn them into business-related topics. Over the years I've bought and read The Art of War by Sun Tzu, The Book of Five Rings by Miyamoto Musashi, Leadership Secrets of Attila the Hun by Wess Roberts, and a collection of Napoleon's Military Maxims by the MBC Library of Military Masters.
I've read leadership books about other famous military leaders, including Eisenhower, MacArthur, and Powell.
Although all of these books celebrate the life or teachings of a military leader, I've found them in the business, management, and leadership sections of bookstores. I think it's easy to repackage military maxims and concepts as business; but they end up requiring interpretation and sounding like pat answers to the difficult questions we face in business.
Knowing that Napoleon recommends two ranks of musketeers instead of three in battle won't help you when you're faced with a difficult business decision. Knowing Sun Tzu's formula for fighting different sized armies won't help you when you're sitting in a boardroom in a presentation.
If you're looking to add a book to your business library, avoid most of the military/business crossover books today. The best one in the above collection is Sun Tzu's The Art of War, but I'd still recommend reading it if you have an interest in history and not to develop business acumen.