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Britain Declares War on Germany WWI

Kaili is a student of history and of WWI. She has researched BEF and Canadian battles and has visited WWI battle sites, including Gallipoli.

As we have seen, there was much pent-up bad will among the major players in this unfolding drama. In the past, they had fought against each other, often many times over the centuries. The Franco-Prussian War. The Anglo-Russian War. The Franco-Austrian War (part of the Napoleonic Wars). This time, Germany and Austria were firmly committed to their alliance. But what about the other part of their Triple Alliance, the Kingdom of Italy? Where were they in this matter? And what would Britain do, particularly if Germany invaded neutral Belgium?

The Triple Entente: Female Personifications of France, Russia and Britain


Alliances and Ententes in WWI

Alliances that were now in place meant that countries like Britain and Russia would come to each other’s aid in time of war. The man behind these alliances was the late King of England, Edward VII. Though it remained the job of the British government to actually hammer out and implement alliances and treaties through diplomatic channels, the King lent his support as a kind of roving Ambassador.

In his short time on the English throne, Edward had strongly supported the government in its formation of alliances with France and Russia, two countries that had been sworn enemies of England in the past. Edward had personally visited France to promote better relations between the two countries, and had met with the Czar of Russian during a state visit. Edward had also been the driver behind an alliance with an emerging country on the world’s stage of powerful countries – Japan.

The Entente Cordiale signed between Britain and France in 1904 had mostly been intended to end long-standing issues between the two over their respective colonies, but was also meant to end the on-and-off hostilities that had marked their relationship over the centuries. Russia joined the two in an alliance called the Triple Entente when it signed the Anglo-Russian Entente in 1907.

The Triple Alliance was an agreement between Germany, Austria and the Kingdom of Italy. Originally signed in 1882, the three promised to lend their defensive support should any member of their alliance be attacked by one of the major powers. In an addendum to the original agreement, Italy declared that it could not commit if actions involved Britain. It later, and in secret, made a similar declaration to France.

A Belgian Outpost

Photo from The Illustrated London News August 15, 1914

Photo from The Illustrated London News August 15, 1914

Germany Implements the Schlieffen Plan

Germany had to cross Luxembourg and Belgium – both neutral countries – in order to fully implement its Schlieffen Plan and score a quick and decisive victory over France by coming into the north of France via Belgium, circling down along the western side of France toward Paris, and then flanking the French armies who would be busy defending France’s eastern border with Germany.

An 1839 Treaty signed by England, Germany (Prussia), Austria, France and Russia declared Belgium to be a neutral state in perpetuity. After the Franco-Prussian War, Britain had also declared that it would come to Belgium’s aid should either France or Germany ever violate Belgium’s neutrality.

After both Alsace and Lorraine had been lost to the Germans in the Franco-Prussian war of 1870-71, France had constructed forts along its common border with Alsace and Lorraine. If Germany tried to attack through that part of France, it would have resulted in a long engagement between the armies and would not have allowed the Schlieffen Plan to play out quickly and before Russia appeared on the scene. To the south lay Switzerland, another neutral country that was also mountainous, meaning movement of large armies through that country would be next to impossible.

Germany had no choice but to attack France through Belgium if its Schlieffen Plan was going to succeed and allow it to encircle the French. The Plan did not anticipate armed resistance by either Luxembourg or Belgium.

Germany Invades Belgium and The Battle of Liege

WWI Timeline

July 28th, 1914 - Austria declares war on Serbia.

August 1st, 1914 - Germany declares war on Russia. Russia defies Germany’s warning to halt mobilization of its troops, replying that the mobilization is only against Austria.

On August 1st, France enters the fray when it orders its army to mobilize to come to the aid of its ally Russia.

August 3rd, 1914 - France declares war on Germany and Germany declares war on France.

Britain delivers an ultimatum to Germany to get out of Belgium by midnight.

August 4th, 1914 – Germany’s invasion of Belgium causes Britain to formally declare war on Germany.

British Ultimatum to Germany 1914

German forces had begun their occupation of Luxembourg on August 2nd, claiming that they had taken this step only as a means of supplying their troops in the fight against France. The tiny Luxembourg army did not resist. As more German troops poured into Luxembourg, Belgium ordered its troops, which had already mobilized, to be on guard and to defend its borders against any hostile forces.

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On August 1st, the German Ambassador to Belgium had actually presented the Belgians with an ultimatum to allow Germany to cross into Belgium, telling the Belgians that France was about to attack Belgium, which was completely false. On August 3rd, when Belgium declined to give Germany permission to move its huge army through Belgium, Germany ignored its response and moved ahead with its plans to attack France through Belgium anyway. Germany declared war on France August 3rd, 1914 and began its invasion of Belgium.

Britain was outraged by Germany’s violation of Belgian neutrality, and let the German Chancellor know this in no uncertain terms. Britain issued its own ultimatum to Germany – get out of Belgium by midnight August 3rd or face the consequences. Germany ignored Britain’s demands, and Britain was forced to declare war on Germany August 4th, 1914.

Britain and her vast Empire were now at war.

British Foreign Minister Sir Edward Grey Addresses Parliament

On Monday, August 3rd, 1914, Sir Edward Grey (the gentleman standing in the image at the beginning of the video below) rose to address the British Parliament. On the subject of Belgian neutrality, he had this to say:

"We have great and vital interests in the independence (of which integrity is the least part) of Belgium...If, in a crisis like this, we ran away from those obligations of honour and interest as regards the Belgian Treaty, I doubt whether, whatever material force we might have at the end, it would be of very much value in face of the respect that we should have lost; and I do not believe, whether a Great Power stands outside this war or not, it is going to be in a position at the end of this war to exert its material strength."

Britain Declares War


  • Anon. (1923) Source Records of the Great War, Volume I. Canada: National Alumni, The Great War Veterans Association of Canada
  • Anon. (1914-1921) History of the War, Volume I. London UK: The Times
  • Tuchman, Barbara. (1962) The Guns of August. New York NY: Macmillan Company
  • The Illustrated London News, August 15, 1914

© 2014 Kaili Bisson


Kaili Bisson (author) from Canada on August 10, 2014:

Thanks so much Deb. There has always been some debate about what would have happened if Britain had not entered the war. I personally think she had no choice.

Deb Hirt from Stillwater, OK on August 10, 2014:

Nice work, Kaili. Short and to the point in easy to understand context.

Kaili Bisson (author) from Canada on August 05, 2014:

Hello billy and thank you for your lovely feedback. WW1 is a passion of mine, so stay tuned...I have drafts for about six WW1 hubs on the go right now.

Bill Holland from Olympia, WA on August 05, 2014:

The good, the bad, and the ugly of world history. I really like this new series of yours. Of course, I'm a former history teacher, so of course I'll like it, right? But it is well-written and I appreciate that.

Kaili Bisson (author) from Canada on August 02, 2014:

Thank you so much for your feedback Mel. Yes, and even more double-dealing was in the sad, all those young men.

Mel Carriere from Snowbound and down in Northern Colorado on July 30, 2014:

Another marvelously composed hub. The tragic thing about WWI is that nobody seems to really know what they were fighting for, yet millions had to die. These entangling alliances are dangerous.

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