Why Germany declared war on Portugal on 9 March 1916

On Thursday 9 March 1916 Baron Rosen, the German minister in Lisbon (the head of Germany's legation, one rank below an ambassador), asked to see the foreign minister, Augusto Soares. Soares gave him six in the evening. Rosen arrived on time, dressed in black with a frock coat and top hat, and Soares's secretary, Eugénio Tavares, showed him in. The meeting lasted no more than 20 minutes.1 source1 source

Lisbon had seen it coming. Germans living in the city had been drawing out their savings and packing for neutral Spain, and the press followed Rosen wherever he went. On the night of 8 March the lights of the German legation on Rua do Século burned until dawn. The newspaper A Capital guessed that papers were being burned.1 source1 source

Rosen left a note. After a long list of grievances it ended in two short sentences: the Imperial Government was forced to draw the necessary consequences from Portugal's conduct, and it considered itself from that moment in a state of war with the Portuguese Government. Portugal had been fighting Germans in Africa for 18 months without being at war with Germany. Now it was.2 sources2 sources

Portugal had been a republic since October 1910. When the war broke out in August 1914 Britain, its most ancient ally, did not ask it to fight. London asked Lisbon not to declare itself neutral, but to stay out of the war as a non-belligerent. On 7 August 1914 the government told Congress, as the two chambers of parliament were called, to unanimous applause, that Portugal would never fail in its duties to the alliance.3 sources3 sources

In Africa the fighting started anyway. Portugal's two big colonies each bordered a German one: Angola had German South West Africa, today Namibia, to the south, and Mozambique had German East Africa, today mainland Tanzania, across the Rovuma river. At the end of the summer a German party attacked the Portuguese post of Maziua on the Rovuma, sacked it and killed the head of the post. The historians Luís Alves de Fraga and João Freire date the attack to 24 August 1914; the government's statement to Congress in 1916 said early September.3 sources3 sources

In southern Angola a shooting at the fort of Naulila in October 1914 brought German raids that autumn and a Portuguese defeat at Naulila on 18 December, a story told in our article on Naulila. By the end of the war Portugal had sent about 18,400 men to Angola and 31,700 to Mozambique, by Carlos Lopes's count.4 sources4 sources

At home the question was whether to go further. The Democratic Party of Afonso Costa wanted Portugal in the war in Europe, because only the war there would decide who kept which colonies. The conservative republicans and much of the public would accept, at most, fighting in Africa. Fraga adds the interventionists' other aims: to make sure of Portugal's independence within the Iberian Peninsula, to depend less on Britain, and to rally the country behind a young and shaky regime.1 source1 source

For more than a year London kept saying no. The historian António Louçã, writing for RTP, dates the change to late 1915, when the war's hunger for men and German submarine sinkings made neutral manpower and neutral shipping worth having.1 source1 source

When the war began, German merchant ships far from home took refuge in neutral ports. One count puts the number that found refuge in neutral waters at 734. Dozens of them were lying in Portuguese harbours, in Lisbon, the islands and the colonies, and they stayed there, idle, for 18 months.3 sources3 sources

By 1916 the Allies were short of ships. The historian Nuno Severiano Teixeira describes an enormous shortage of tonnage on the Allied side, while the German ships in Portuguese ports came to about 240,000 tons. Portugal was short too: Lisbon's own case was that the idle ships were needed for its trade.3 sources3 sources

Afonso Costa had returned as prime minister at the end of 1915, at the head of a government beset by shortages, strikes and riots. On 7 February 1916 it passed Law 480, which allowed the state to requisition at any time the raw materials and means of transport the country needed. On 10 February Leote do Rego, a naval officer and deputy, wrote in O Século that the government should not hesitate to use the German steamers.2 sources2 sources

Britain's request mattered at home. As the Unionist leader Brito Camacho told Congress on 10 March, once Britain asked in the name of the alliance for something Portugal could do, Portugal could not refuse.1 source1 source

On the morning of 23 February 1916 the government issued Decree 2,229, which ordered the requisition in the interest of the national economy and its sea transport. Its fifth article promised the owners compensation, the amount to be fixed later. The same day Soares telegraphed the Portuguese minister in Berlin to tell the German government.2 sources2 sources

At 5.50 pm the cruiser Vasco da Gama fired a 21-gun salute on the Tagus. The commander of the Naval Division boarded the destroyer Douro and led a flotilla of the destroyer Guadiana and two torpedo boats among the German ships. On each one the German flag came down and the Portuguese flag went up with a war pennant. RTP's account names Leote do Rego as the officer in charge and says no one used force. The weekly Ilustração Portuguesa put the number taken in the Tagus at 36. The ships in the other ports were taken over in the following days.3 sources3 sources

The German captains said they were surprised, then handed over letters of protest written weeks before, with only the date filled in. Inspecting them, the Portuguese found the engines of most of the ships damaged, with parts hidden, thrown overboard or smashed, and two ships' engines booby-trapped to explode. Some repairs took a year.1 source1 source

On 27 February Rosen protested at a singular breach of law: Portugal had taken the German ships by an act of force, without any prior negotiation. He asked for the measure to be revoked at once. Lisbon refused. Its reply argued that ships sheltering under Portuguese protection for 18 months fell under the state's right of eminent domain, that Italy had done the same without German objection, and that the owners would be paid.1 source1 source

Rumours of a German ultimatum ran through Lisbon from 28 February, and the government denied them. On 2 March Sidónio Pais, Portugal's minister in Berlin, telegraphed that war could still be avoided if Lisbon promised the ships would not go to Britain. That was a promise Lisbon could not give.2 sources2 sources

The declaration of 9 March listed what Berlin held against Portugal since 1914. British troops had been let through Mozambique four times; German ships had been refused coal; British warships had stayed in Portuguese ports and used Madeira as a base; guns and a destroyer had been sold to the Entente. It accused Portugal of luring a German official and two officers to Naulila and shooting them, and it complained of insults to the Kaiser in Congress. Then it came to the ships.1 source1 source

Portuguese historians have tended to agree that Lisbon wanted this outcome. Teixeira calls Lisbon's course a strategy of provocation, and Fraga writes that the declaration was above all the result of a manoeuvre by Portuguese diplomacy. London put the blame on Berlin. The British government's statement to the Commons on 14 March said Portugal's action would have been justified even for a neutral, that Britain had urged the requisition too, and that Germany had chosen to precipitate matters.3 sources3 sources

That evening President Bernardino Machado signed a decree calling both chambers of Congress to a joint session the next day at 4 pm. The session opened at 4.55 pm on 10 March with 184 members present and the president in his box. One deputy telegraphed from Benavente that floods and a storm had stopped him crossing the Tagus. The galleries were packed, and diplomats from nine countries, among them the ministers of Britain, France, Russia, Belgium and Italy, watched from the diplomatic box.2 sources2 sources

Soares read the documents aloud, the British note and the German declaration included, and apologised for not leaving out the German note's unusual language. Costa then put a one-line resolution: Article only. The Executive Power is granted all the powers needed for the state of war with Germany, under Article 26, no. 14 of the Constitution.1 source1 source

Every party spoke for it. António José de Almeida of the Evolutionist Party called on all Portuguese to unite and hoped for a sacred union. Brito Camacho asked for an inquiry to clear Portugal's officers of the Naulila charge. For the Socialists, José António da Costa Júnior said his party had always fought war as a calamity but that every true socialist now stood with the country. Costa's resolution and a motion for a national government both passed unanimously. The session closed at 6.35 pm to cries of long live the Republic.1 source1 source

That night Rosen left Lisbon for Madrid on a special train with his wife, his staff and some German residents. Many other Germans stayed. On 12 March Decree 2,270 let the authorities stop newspapers from circulating on grounds of national defence. By the end of the month this had become prior censorship, and papers appeared with blank spaces where articles had been cut.2 sources2 sources

London answered on 12 March. The British minister, Lancelot Carnegie, passed on a message from the foreign secretary, Sir Edward Grey: Britain would stand by Portugal against the common enemy and give it all the help possible or necessary. On 14 March Grey read the prime minister's statement to the House of Commons.2 sources2 sources

Costa resigned the day after the vote and stayed on as caretaker. On 15 March the Chamber of Deputies heard a letter from António José de Almeida, leader of the Evolutionists: the president had asked him to form the national ministry. The new government came to parliament the next afternoon.3 sources3 sources

It joined Costa's Portuguese Republican Party, known as the Democrats, and Almeida's Evolutionists. Brito Camacho's Unionists promised support but stayed out. Almeida became prime minister and minister for the colonies, and Costa took the finance ministry. Finding a leader had not been easy: several men were approached first and declined, among them the poet Guerra Junqueiro.4 sources4 sources

Almeida's declaration gave parliament more news: Austria-Hungary had broken off relations the day before, without giving a reason. It was not a declaration of war: the American minister, Thomas Birch, cabled Washington that morning that there had been none. Almeida promised a new Ministry of Labour and tolerance towards the Republic's opponents. Then he gave the government its name.2 sources2 sources

The Sacred Union government lasted from March 1916 to April 1917. Almeida, who had been Costa's rival for years, made his peace with him to lead it.2 sources2 sources

The first fighting was in Africa again. From April 1916 Portuguese troops in northern Mozambique went on the offensive towards the Rovuma and the Kionga triangle, a strip south of the river's mouth that Germany had held since 1894. João Freire judges the offensives beyond the river badly planned and badly carried out, and they ended in failure.2 sources2 sources

In Portugal some 20,000 men were called up in the spring and summer of 1916 and trained as a division at the Tancos firing range, an effort the war minister, Norton de Matos, called the miracle of Tancos. In the summer Costa and Soares went to the Allied economic conference in Paris and then to London, to learn what Britain expected of Portugal at war and to settle questions of money.4 sources4 sources

On 7 August 1916 Congress resolved to give the invitation full satisfaction. The details were settled in a convention with Britain signed on 3 January 1917, and the first contingent of the Corpo Expedicionário Português sailed from Lisbon on 30 January. Some later accounts say 26 January. Its worst day came at La Lys on 9 April 1918, when between 398 and 614 men were killed, by different counts, and about 6,585 taken prisoner.6 sources6 sources

The ships were renamed and most of them ended up serving Britain. Many were sunk by German submarines. Portugal also borrowed from Britain to pay for its war: by António José Telo's figures, quoted by RTP, the credit line stood at £15.6 million in 1918, and by 1925 the debt had grown to £22.7 million.1 source1 source

Teixeira's verdict is that Lisbon got what it went to war for in Africa. Portugal sat among the victors and, through the Treaty of Versailles, gained the Kionga triangle. It also won the right to claim for German attacks before 9 March 1916; Swiss arbitrators ruled in 1928 that the Naulila raids had been unlawful.2 sources2 sources

At home the Sacred Union did not last. The war had been meant, in part, to rally the country behind the Republic. In December 1917 Sidónio Pais, the envoy who had been in Berlin until the declaration, seized power in Lisbon, and after that, Fraga writes, no more reinforcements reached the corps in France.3 sources3 sources

On paper Portugal did not choose the war: Germany declared it. The record shows how much Lisbon did to bring that about, and historians still weigh a British request against a Portuguese plan. The documents to judge it are public: the debates of 10 March 1916, with the British note and the German declaration, can be read in full on the Assembleia da República's website.4 sources4 sources

Much of the rest of Portugal's war began in these weeks: the Sacred Union's promise of national unity, the reliance on British ships and money, and the road to the trenches of Flanders.3 sources3 sources