| Term | Definition |
| Napoleon III | Emperor of France who was defeated in the Franco-Prussian War. |
| William I | Ruler of Prussia, who made Otto von Bismarck a chancellor. Later became Kaiser of all of Germany. |
| Otto von Bismarck | Prime minister of Prussia. Led Prussia to victory against Austria (1866) and France (1870) and was responsible for the unification of the German states. |
| Prussia | German state which led the unification movement and was the most powerful portion of the newly-created Germany. |
| Austria | German state which tried to stop unification and never became part of the German Empire. |
| Denmark | Nation with which Austria and Prussia fought over smaller German states. |
| Schleswig-Holstein | German states controlled by Denmark which Prussia was able to win in a series of wars. Their acquisition brought Germany closer to unification. |
| Franco-Prussian War | Last step in German unification because it brought the southern German states together with the North German Confederation in defense against France. |
| North German Confederation | Result of end of Austria-Prussian War, Austria doesn't get involved in German affairs, North German Confederation made under rulership of Prussia. Major step towards German unification. |
| 1870-71 | Germany and Italy finally become united nation-states. |
| realpolitik | politics based on practical rather than moral or ideological considerations |