For the complicated politics of the European alliances before 1914, I have been especially indebted to J. M. Roberts Europe 1880-1945, 2nd edition (Longman, 1989) and to Michael Rapport, Nineteenth-Century Europe (Palgrave, 2005).
'In the approach to the outbreak of the First World War, four factors were crucial: first, the ambitions and strategies of the great powers; second, the system of alliances, the danger of which was less to drag allies into the abyss than to make them concerned lest their opposite numbers renege on their commitments at the last moment; third, the balance of power in the decision-making process between military men and civilian politicians; last, the pressure of both nationalist and socialist anti-militaristic opinion, and the opportunity offered by the war to achieve the ultimate in national integration'. Robert Gildea, Barricades and Borders: Europe 1800-1914, 3rd edn. (Oxford, 2003), 429.
Between the Berlin Congress of 1878 and 1900 the Concert of Europe in effect came to an end as new occasions of conflict arose.
The condition of the military
Among the great powers of 1880 only Britain was not a land power. To continental countries armies were more important than navies. Military thinking was still obsessed with the idea of winning a decisive battle soon after the outbreak of war. It was assumed that wars would be short (as they had been in 1866 and 1870) and the five year experience of the American Civil War was discounted.