Who used the phrase blood and iron to unify Germany?

The phrase "blood and iron" was famously used by Otto Von Bismarck, the Prussian statesman, during a speech in 1862. He emphasized that the unification of Germany would not be achieved through speeches and democratic processes but rather through military force and pragmatic policies. Bismarck's approach ultimately led to the successful unification of Germany in 1871, solidifying his role as a key architect of the new German Empire.