Answer:

He was the chief architect of the unification.

He achieved this by fighting 3 wars-all victorious:

1)He defeated Denmark and annexed Shleswig-Holstein (1864).This favourably impressed public opinion in Germany as this was an all German cause.

2)He defeated Austria (1866) and this eliminated Austrian interference in German affairs.Northern Germany became part of the Prussian controlled North German Confederation (est.1867).And even the 4 nominally independent South German states-Bavaria,Baden,Wirttenberg,and Hesse-Darmstadt were under strong Prussian influence.They all had offensive+defensive military alliances with Prussia.

3)He defeated France (1870–71)Although the armies were Prussian led,this was an all-German war as the other German states,including the southern ones,placed their own armies under Prussia’s command.The spectacular victories created a ground swell of patriotism all over Germany.On behalf of the German princes ,Bavaria offered the King of Prussia the throne of a united Germany (Jan.18,1871).Wilhelm 1 accepted and thus was born the German Empire-or Second Reich.(The First Reich was the Holy Roman Empire.)

Explanation:

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