<P> The Zollverein ((ˈtsɔlfɛɐ̯ˌʔaɪn)) or German Customs Union was a coalition of German states formed to manage tariffs and economic policies within their territories . Organized by the 1833 Zollverein treaties, the Zollverein formally started on 1 January 1834 . However, its foundations had been in development from 1818 with the creation of a variety of custom unions among the German states . By 1866, the Zollverein included most of the German states . The foundation of the Zollverein was the first instance in history in which independent states had consummated a full economic union without the simultaneous creation of a political federation or union . </P> <P> Prussia was the primary driver behind the creation of the customs union . Austria was excluded from the Zollverein because of its highly protected industry and also because Prince von Metternich was against the idea . By the founding of the North German Confederation in 1867, the Zollverein covered states of approximately 425,000 square kilometres, and had produced economic agreements with several non-German states, including Sweden - Norway . After the founding of the German Empire in 1871, the Empire assumed the control of the customs union . However, not all states within the Empire were part of the Zollverein until 1888 . Conversely, Luxembourg was independent and not a state in the German Reich, it remained in the Zollverein until 1919 . </P>

When was the custom union known as zollverein formed and with what purpose
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