584-593 (small edition); Spencer Walpole, _Life of Lord J.Russell_, vol.ii.pp.

396-411.
In several respects the cause of ruin to Denmark in 1863-64 bears a remarkable resemblance to that which produced war in South Africa in 1899, viz.

high-handed action of a minority towards men whom they treated as Outlanders, the stiff-necked obstinacy of the smaller State, and reliance on the vehement but (probably) unofficial offers of help or intervention by other nations.
The question of the sharing of the Duchies now formed one of the causes of the far greater war between the victors; but, in truth, it was only part of the much larger question, which had agitated Germany for centuries, whether the balance of power should belong to the North or the South.

Bismarck also saw that the time was nearly ripe for settling this matter once for all in favour of Prussia; but he had hard work even to persuade his own sovereign; while the Prussian Parliament, as well as public opinion throughout Germany, was violently hostile to his schemes and favoured the claims of the young Duke of Augustenburg to the Duchies--claims that had much show of right.

Matters were patched up for a time between the two German States, by the Convention of Gastein (August 1865), while in reality each prepared for war and sought to gain allies.
Here again Bismarck was successful.