The Portuguese Expeditionary Corps (CEP, Portuguese: Corpo Expedicionário Português) was the main military force from Portugal that fought in the Western Front, during World War I. Portuguese neutrality ended in 1916 after the Portuguese seizure of German merchant ships resulted in the German Empire declaring war on Portugal. The expeditionary force was raised soon after and included around 55,000 soldiers.
Background
At the outbreak of the First World War, Portugal had declared its neutrality. The country remained neutral until 1916, though occasional skirmishes between Portuguese and German colonial troops occurred in Africa. In March 1916, the Portuguese Government seized a number of merchant ships belonging to the Central Powers which were anchored in Lisbon. The German government took this as a hostile act and declared war.
The Government announced it would raise an expeditionary force to fight on the Western Front, with the first units being raised by July. In early 1917, the force was split into two elements: Portuguese Expeditionary Corps (Corpo Expedicionário Português or CEP) – an infantry force of about 55,000 men, to operate under the control of the British First Army; Independent Heavy Artillery Corps (Corpo de Artilharia Pesada Independente or CAPI) – an artillery force of nine batteries of heavy railway guns, manned by Portuguese gunners with artillery provided by France and the United Kingdom, to operate under the control of the French Army.
Initially, CEP was constituted as a single reinforced infantry division, organized according to the Portuguese model, in which divisions were much larger than the British ones. Subsequently, it was decided to reorganize the CEP according to the British model, allowing it to become an army corps of two divisions and corps support troops, just by adding some additional battalions. This new organization would allow it to have sufficient autonomy to be able to take the responsibility for an entire independent sector of the Western Front.
Deployment of the CEP
The CEP was shipped to France in early 1917, where the first groups received training in trench warfare and were equipped with British small arms. The first units began to deploy in May, and a sector of the frontline was fully held by the CEP by November; by the end of October, just under 60,000 troops had been sent to France.
From 6 November 1917, CEP took charge of the whole "Portuguese Sector" of the Western Front, with a total frontage of . In accordance with Allied practice, the sector included three lines of defense. The first included the front line (A-Line), the support line (B-Line) and the reserve line (C-Line). The second included the village line (brigade headquarters line) and the corps line. Finally, the army line formed the third line of defense.
The Portuguese Sector was divided into four brigade sectors. Each brigade deployed two battalions at the front (each defending a sub-sector of the brigade sector), one in support and another in reserve. Each of the CEP's two divisions controlled two brigade sectors, with a third brigade in reserve.
Combat service until the Lys
CEP suffered the first German attack on 4 June 1917, made against Neuve-Chapelle sector. The attack was repelled by the 35th Portuguese Infantry Battalion, which had deployed to the front trenches just two days before. On the night of 12 June, a more intense German attack was carried out against Ferme du Bois and Neuve-Chapelle sectors, being repelled by the 2nd, 3rd and 7th infantry battalions.
On 14 August, the Germans launched a strong attack against the Portuguese lines. After an intense artillery bombardment, a Stosstruppen battalion assaulted the Neuve-Chapelle and Fauquissart sectors. In the defence against this attack, 2nd Lieutenant Hernâni Cidade of the 35th Infantry Battalion stood out, being able to capture several German prisoners, including the captain who led the assault. In another German assault on 14 September, 2nd Lieutenant Gomes Teixeira, of the 7th Infantry Battalion, led a counterattack with his platoon, killing the German commander and other men and capturing four prisoners. Another 2nd Lieutenant, David Neto from the 4th Infantry Battalion, only supported by his orderly, captured an entire German patrol made up of one officer and seven men on 13 December. For the actions of these officers, the A-Line (Front Line) became known by the Portuguese troops as the "Line of the 2nd Lieutenants".