The First World War had a profound impact upon British society. It swept away much of the old Victorian and Edwardian order and established many of the features that we associate with 'modern' 20th-century Britain. The scale and duration of the conflict with the Central Powers was such that, for the first time, the whole of British society was mobilised for what historians have termed 'total war'.

These changes did not take place overnight in August 1914. It was a gradual and cumulative process, governed more by reactions to events than by any grand strategy. The central agent of change was the British state. In the early stages of the war, its role was largely confined to security issues such as the Defence of the Realm Act, censorship and aliens. But from 1915 onwards, state power was extended into new areas.

By 1915 there was a pressing need to mobilise greater human resources to keep pace with escalating production demands in the war industries. The 'shell scandal' of May 1915 revealed that competing firms were producing poor-quality munitions in wholly insufficient numbers.

The Asquith government subsequently created the first of the new war ministries, the Ministry of Munitions under Lloyd George, which intensified munitions production with considerable success. Output increased enormously. Up to April 1915, just two million rounds of shells had been sent to France. By the end of the war, that figure stood at 187 million rounds.

The acute labour shortage that became apparent in 1915 also led to another radical departure from the pre-war order: the large-scale employment of women in industry. From 1 June 1915 - when they were first employed in munitions factories - to the end of the war, at least one million women were added to the British workforce. Half of them were employed in manufacturing jobs, largely in the munitions industry, that had previously been seen as an almost exclusively male domain.

The important contribution of women to the war effort was at least partially recognised in the 1918 Representation of the People Act, which extended the franchise to women over the age of 30.