Dear Student, Unification of Germany was officially announced on 17 January 1871. The whole unification process is described as below :-
Before the unification of Germany the nationalist sentiments were organised by the conservatives to promote the state power and to maintain their dominance in the society.
The middle class Germans tried to unite different parts of Germany but they failed to do so. The main reason was the high class Germans known as Junkers of Prussia ( Prussia in ancient name of Germany).
After that, Prussia won wars with Austria, Denmark, and France after seven years. After it, William I became the king of Prussia.
In January 1871, the Prussian king, William I, announced that Germany will be unified. In this way, all parts of Germany were united.
The major importance was given to the mordenisation of currency, trade , banking and judicial system.