Trench warfare
Trench warfare prevailed on the Western Front from late 1914 until the Germans launched their Spring Offensive on 21 March 1918. After the buildup of forces in 1915, the Western Front became a stalemated struggle between equals, to be decided by attrition. Frontal assaults, and their associated casualties, became inevitable because the continuous trench lines had no open flanks. Casualties of the defenders matched those of the attackers, as vast reserves were expended in costly counter-attacks or exposed to the attacker's massed artillery. There were periods in which rigid trench warfare broke down, such as during the Battle of the Somme, but the lines never moved very far. The war would be won by the side that was able to commit the last reserves to the Western Front.
Aisne
It is thought that the Aisne River was the birthplace of the trench warfare seen in the First World War. The British Expeditionary Force (BEF) had initial early successes driving the Germans back to the Aisne River; the German troops dug in and managed to hold out against both British and French attacks. This German entrenchment was to mould the entire face of World War One as both sides began digging in and fortifying their positions. Thus began the stalemate that became a significant feature of the First World War.This linguistic variance probably explains the difficulty for residents south of Aisne to identify themselves as belonging to the Picardy region.
In 2008, the department had 4.1% of second homes. This table shows the main communes of Aisne that have second homes which occasionally exceed 10% of total housing.