A first national liberal parliamentary group arose among right-wing deputies of the liberal German Progress Party in the Prussian House of Representatives during a constitutional conflict sparked by Minister President Otto von Bismarck: In 1862, he had overruled the Liberal opposition in parliament using the so-called "Lückentheorie" ("Gap Theory") to justify proceeding with taxes for military reforms of the Prussian Army, accompanied by his martial "Blood and Iron" speech.