# Prussia and Austria open the war against Denmark over Schleswig-Holstein

Date: 1864

## The fact

In February 1864 Prussian and Austrian troops entered Schleswig after Denmark’s November Constitution tied Schleswig more tightly to the kingdom. [Bismarck](/people/otto-von-bismarck) had chosen an Austrian alliance instead of a purely nationalist volunteer war. The campaign included the storm of Düppel. This is one Danish-war Fact, not a twin of Königgrätz. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

## Context

The London Protocol of 1852 and the Danish succession after 1863 were the legal tangle. Liberal German nationalists wanted a Augustenburg duke. Bismarck wanted Prussian control without a liberal revolution. Civilian costs in Jutland and the duchies were real and limited compared with 1870. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

The attached driver is [humanitarian-access](/drivers/humanitarian-access). The welfare reading used in this dossier is worsening. That reading is an impact-path choice, not a property stored on the Fact itself.

## Evidence and sources

GHDI publishes 1864 intervention documents. Britannica independently dates the German-Danish War. Moltke’s staff histories independently reconstruct Düppel. No Factrail original casualty census is supplied. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

Official or archival record: GHDI — Austro-Prussian intervention in the duchies, 1864 (https://germanhistorydocs.ghi-dc.org/sub_document.cfm?document_id=343; German History in Documents and Images).

## Significance

Worsening humanitarian path of a cabinet war. Complex contribution. High confidence on the diplomacy; medium on any one casualty total. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

Shared responsibility is part of Prussia and Austria open the war against Denmark over Schleswig-Holstein. Naming Otto von Bismarck does not delete co-authors, institutions, or later transmitters. The lag from 1864-02-01 to any measured indicator is not treated as zero. Alternative explanations — weather, other armies, later statutes, or independent cultural change — remain live where the sources do not close them.

## What is established and what is not

Established: Prussia and Austria made war on Denmark in 1864 with Bismarck as Prussian foreign minister. Not established: that he commanded the storming columns, or a unique death total. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

If a number is not in the two records named above, it is not supplied here.

Later competitions, monuments, translations, UNESCO listings, museums, and adaptations are not converted into extra lifetime acts.

Confidence is stated on the impact path, not hidden in adjectives. Do not treat 1864 as 1866. Do not treat Gastein as a second war Fact. Mixed effects of Prussia and Austria open the war against Denmark over Schleswig-Holstein are separate paths.

## People

- Otto von Bismarck: https://factrail.ai/people/otto-von-bismarck

## Drivers

- Humanitarian Access: https://factrail.ai/drivers/humanitarian-access

## Sources

- https://www.britannica.com/event/German-Danish-War
- https://germanhistorydocs.ghi-dc.org/sub_document.cfm?document_id=343

## Methodology

https://factrail.ai/methodology

Canonical: https://factrail.ai/facts/de-bismarck-danish-war-1864