Lesser Germany

The German National Assembly also installed a provisional head of state (the uncle of the Austrian Emperor) and government.

Austria rejected demands for such a division of its imperial territory, as it viewed a personal union as insufficient to ensure integrity of the monarchy.

It also made for the first time a then-failed attempts to expand borders of the Confederation through inclusion of the original nucleus of Prussian statehood (East Prussia), as well as through annexing into the Confederation the Prussian-ruled share of the dismembered Polish state, enjoying a degree of autonomy and consisting of Pomerelia (renamed West Prussia), the Lauenburg and Bütow Land, as well as the Greater Poland (renamed Grand Duchy of Posen).

The planned annexations elicited an immediate armed response of the Poles in the form of the Greater Poland uprising (1848) and were as a result abandoned for the time being.

In an unexpected turn of events, the Prussian king refused, however, to accept in April the offered crown of the nascent German Empire (1848–1849), primarily due to his negative perception of the form of the planned empire as designed by the Frankfurt Constitution, thus causing abortion of the efforts to establish the state.

Joseph von Radowitz, adviser to the Prussian king and actual leader of the project, tried to bind Austria and the Union together in a confederation.

Austria came out weakened by the Italian War of the previous year while Prussia sought to gain the approval of the national movement.

Although hailed as a German success at the time, the annexations were in fact a Pyrrhic victory, because along with the ensuing Germanisation, the Kulturkampf and the Prussian deportations, they alienated decisively and irrevocably the Polish majority living in these territories from the Hohenzollerns as well as eroded any confidence or loyalty of Poles towards the State of Prussia.

In the peace treaty with Austria, and already before with France, Prussia promised not to expand the North German state to southern Germany.

Austria did not dare to support France because of its weak position after the war of 1866 and because of the German-speaking inhabitants sympathizing with the German cause.