New Order or Old Blood, Which to Play First?

To clarify (horribly most likely), is it better to start off my first Nazi Hunting Journey^TM with New Order (the first game) or Old Blood (the first narratively)?

I figure New Order, being the first game, would introduce me to the world and characters while Old Blood would likely show and explain some of the motivations and background of New Order.

So I ask for the opinion of others, for I am at a loss of where to begin, and Danke for your opinions.