The Kingdom of Prussia dominated northern Germany politically, economically, and in terms of population, and was the core of the unified North German Confederation formed in 1867, which became part of the German Empire or Deutsches Reich in 1871 when the southern German states, excluding Austria, were added. Prussia attained its greatest importance in the 18th and 19th centuries. During the 19th century, Chancellor Otto von Bismarck pursued a policy of uniting the German principalities into a "Lesser Germany" which would exclude the Austrian Empire.