One of the most profound events in human history, the First World War, marks its hundredth anniversary in 2014. People across the world commemorate the fighting and mourn the countless losses every year, eager to ensure that no such tragedy befalls humanity again. This introduction is presented chronologically, breaking the war down into its catalyst and each year of its development, its aftermath and legacy. Through fascinating contemporary images and concise, riveting narrative, it explores elements that vary from the poetry and correspondence of those serving to the technological developments that helped make the First World War the first ‘modern’ war.