Complex sentence: In 1866, Austria was completely defeated in the Austro-Prussian War and its position as the leading state of Germany ended forever, as the remaining German minor states were soon absorbed into the German Empire created by Prussia.
Split into simpler sentences: In 1866, Austria was completely defeated in the Austro-Prussian War. Austria's position as the leading state of Germany ended forever, as the remaining German minor states were soon absorbed into the German Empire created by Prussia.