In the Austro-Prussian War, France saved Prussia's bacon after the Austrian victory at Koniggratz.
France, having had troops stationed in Lombardy since 1859, seized Veneto, South Tyrol, Istria, Parma, and Tuscany from the Austrians and Hapsburgs and proclaimed the Kingdom of Italy (much to the chagrin of the Savoys who would soon lose Piedmont).
France claimed the southern Triangle of the Rhineland, protected Prussia from other territorial cessions to Austria (with Prussia gaining Schleswig-Holstein and Saxony in exchange for a cession of the North Rhineland to the Wettins) and with Prussian diplomatic support would purchase Luxembourg the following year.
France gained territory and influence, Prussia was bolstered, and Austria was weakened. Germany from henceforth would be divided between the Rhenish Confederacy, Prussian-dominated East German Confederation, and the South German Bloc.
What if France hadn't saved Prussia?