Oh, and the Deutschlandlied‘s words were an exhortation, yes, to estimate the whole country, not just the numerous principalities and kingdoms created by the Congress of Vienna which constituted the German Confederation.
Heinrich Hoffmann von Fallersleben, the author, wanted a German republic in the style of France, with popular sovereignty in the British-American mold.
That was not going well with the neo absolutist princes and princelings, so Hoffmann went into exile. In the German Revolution of 1848/9, at last a big step was done towards democratic rights.
True, but classical liberalism never attained national power in Germany until after WW II. Bismark famously coopted German liberals by adopting the first national pension scheme in the late 1880s, a major step toward the modern welfare state.