Caillaux, Joseph (1863-1944) Leading French radical politician. The trial of his second wife for the murder of the editor of Le Figaro was the major topic of political discussion in France in the summer of 1914.

Cambrai Town in the Nord-Pas-de-Calais region of N France. Scene of the first large-scale deployment of tanks in warfare, when British forces attacked the Hindenburg Line to the west of Cambrai (20 November-7 December 1917).

Cameroon German colony in Central Africa, bordering Nigeria and French Equatorial Africa. After overcoming stout resistance, Allied forces occupied the capital Yaoundé on 1 January 1916. After the war, it became a mandate territory divided into British and French areas of control.

Canadian Corps Formed in September 1915 when a second division of Canadian troops arrived at the Western Front; served with particular distinction at Vimy Ridge (9 April 1917) and during the Allied counter-offensive in the summer and autumn of 1918.

Canal du Nord Canal in NE France, fully completed in 1965. Crossed in a daring assault by Canadian Corps troops during the Allied counter-offensive on the Western Front (27 September-1 October 1918).

Cape Helles Series of beaches on the southern tip of Gallipoli; one of two sites for the Allied landings on the peninsula on 25 April 1915.

Caporetto Italian (now Slovenian) village; Slovenian name: Kobarid. Scene of a crushing Italian defeat at the hands of Austro-German forces (24 October-12 November 1917).

Carpathians Mountain range in central and eastern Europe, extending from present-day Slovakia to central Romania.

Casement, Sir Roger (1864-1916) Former British diplomat and Irish nationalist. Executed for treason on 3 August 1916 for his part in organising the Easter Rising, 24 April 1916.

Caucasus Mountain range in SW Russia, running along the northern border of present-day Georgia and Azerbaijan; between the Black Sea and the Caspian Sea.

Cavell, Edith (1865-1915) British nurse. Executed by the Germans in occupied Belgium on 12 October 1915 for helping Allied prisoners to escape. Her case was quickly adopted by Allied propaganda as an example of German barbarity.

Cenotaph Monument in Whitehall, London, honouring the dead of both world wars. Designed by Sir Edwin Lutyens and erected in 1920.

Central Powers Alliance of Germany and Austria-Hungary during the First World War; later joined by Turkey and Bulgaria.

Chantilly Town and holiday resort in Picardy, northern France. The French army's Grand Quartier Général (GQG), it was the site of the Allied conference in December 1915 at which an agreement for a major Anglo-French offensive on the River Somme in 1916 was made.

Chief of the Imperial General Staff Up to the end of the Second World War, the professional (military) head of the British army.

Childers, Erskine (1870-1922) Author of the popular pre-war spy novel The Riddle of the Sands (1903), in which the two heroes stumble across a German plan to invade England. Despite serving with the British army in the First World War, he later joined the IRA and was executed by firing squad in Dublin in 1922.

Churchill, Winston (1874-1965) First lord of the Admiralty, 1911-15; chancellor of the Duchy of Lancaster, 1915; commanded a battalion on the Western Front, 1915-16; minister of munitions, 1917-19; war (and air) secretary, 1919-21.

Cilicia Region of SE Asia Minor that formed part of the Ottoman empire in 1914; known today as the southern Turkish province of Adana.

Clemenceau, Georges (1841-1929) French prime minister, 1906-09 and 1917-20. Appointed prime minister in November 1917 in the aftermath of the failed Nivelle offensive and the French army mutinies, he promised a more forthright prosecution of the French war effort. Remembered as 'Father Victory', he also led the French delegation that negotiated the Treaty of Versailles in 1919.

Committee of Imperial Defence (CID) Established permanently for the first time in 1904 as the government body charged with organising Britain's defence and military preparations. Its staff always included the prime minister, the war secretary, the commander-in-chief of the British army and the first sea lord. During the First World War, its duties were largely taken over by a War Council drawn from Cabinet members and it did not resume full operations until 1922.

Committee on Alleged German Outrages Committee formed in December 1914 under the stewardship of Lord Bryce to investigate allegations of German war crimes in occupied Belgium. The report of its findings, which accused the German army of a wide range of horrific atrocities, was published in May 1915.

Compiègne City in northern France, on the River Oise. Scene of the armistice between Germany and the Allies that ended the First World War on 11 November 1918. Also the scene of the signing of the Franco-German armistice in June 1940.

Constantinople Capital of the Ottoman empire until its collapse in 1918. The name, by which it had been known since AD 330, was changed to Istanbul in 1926.

Convoy system Naval strategy based on a collection of ships travelling under armed protection. Used systematically by the Royal Navy from June 1917 to safeguard Allied merchant and military shipping against German submarine attacks.

Coronel Area of Atlantic coastline off Chile. Scene of a German naval victory over the Royal Navy on 1 November 1914.

'Coupon election' Term by which the first post-war election in Britain on 14 December 1918 is commonly known. It referred to the 150 Liberal candidates who gave a pledge (called a 'coupon' by Asquith) to support the Lloyd George coalition, which was returned to office in a landslide victory.

Ctesiphon Ancient city on the River Tigris in Mesopotamia. Scene of British defeat at the hands of Turkish forces (22-26 Nov 1915).

Czech Legion Originally Habsburg POWs, this group of roughly 70,000 Czechs and Slovaks was trained and funded by the Allies to fight against the Central Powers on the Eastern Front during the First World War. Trapped in Russia amid the chaos of the post-revolutionary period, the Legion clashed with Bolshevik forces in May 1918, thereby inadvertently providing the catalyst for the Russian civil war.