England (and its succeeding states) were at war with France for close to 1000 years. First it was over land, then they competed over religion, then they competed over colonies.

For much of that time, England was allied with various German states.

All of a sudden, in World War 1 the UK found itself an ally with France and at war with Germany.

What caused this change?

  • 7
    The Triple Entente is a good starting point.
    – HDE 226868
    Commented Jan 13, 2015 at 3:02
  • 4
    The balance of power argument: Yes Minister (video).
    – Nathan
    Commented Jan 13, 2015 at 23:49
  • Many British leaders favoured a German rather than french alliance but attempts broke down, it was only after the failure of securing a German understanding that one with France was sought.
    – pugsville
    Commented Jan 15, 2015 at 4:09
  • 5
    @Nathan Cooper. One of my favourite YM quotes. "Sir Humphrey Appleby: Minister, Britain has had the same foreign policy objective for at least the last 500 years: to create a disunited Europe. In that cause we have fought with the Dutch against the Spanish, with the Germans against the French, with the French and Italians against the Germans, and with the French against the Germans and Italians. Divide and rule, you see. Why should we change now, when it's worked so well?"
    – Jaydee
    Commented Jan 15, 2015 at 11:33
  • The british knew that they inherited much of their culture from france, because all of britain was ruled by 170 dukes from normandy when the magna carta, book of british law, was written by a frenchman called Montfort. The king of england would visit the king of the franks at some times, i think henry 8th did at least, and then 100 years war was the worst episode which started as a family feud, and after 1400, the two countries were relatively free of banditry and mayhem and famines and united and lawful, not always at war. there were many treaties prior to the post napoleonic treaties. Commented Aug 2, 2015 at 22:26

7 Answers 7


British policy on the continent has traditionally been to maintain the balance of power (this is also really a general European thing). This amounted to shifting alliances all over the continent. Though France and Britain are "traditional" enemies (as neighbours were wont to be in Europe), they certainly hadn't been at war for anywhere near "close to 1000 years".

In fact Britain allying with France isn't that unusual. England supported the League of Cognac, an alliance of France and some Italian states against Germany and was close to joining. Britain and France were on the same side against Spain several times, including the War of Portuguese Succession, the Carlist War, and the War of the Quadruple Alliance. In the 17th century there was an abortive alliance under the Protectorate. In the 18th century another alliance was relatively successful against Russians. And in the 19th century, Anglo-French troops fought together against Russia in the Crimean War.

A key change after the mid-19th century is the emergence of Germany as the continent's dominant military, economic and industrial power. This is particularly demonstrated by her victory over France in 1870. It was pretty natural for Britain to seek counterbalancing allies.

  • 2
    Not to mention Edward VII's francophilia who anecdotally, aged 13, asked Napoleon III whether he could be "his son" and who kept all his life a deep attachment to France (and managed to be loved in Paris even by hard die republicans). A convenient circumstance that helped support the geopolitical interest in the public opinion on both side of the English channel. Commented Jul 8, 2015 at 21:07

I agree with much of Semaphore's answer, which shows that actually Britain and France were not in a state of perpetual war.

But I think your question really relates to "What changed?" so I'll try to answer that.

Firstly, the end of the Napoleonic era. The Battle of Waterloo and following months were the end of the Napoleonic wars, and the end of the "Big" conflict between Britain and France, that of Empire and Conquest.

These wars had been, for over 100 years, about trying to take the "best" territories, colonies, etc. from each other (And in this I include Britain, Spain, Portugal, France and The Netherlands, plus Russia, Sweden, Austria to a lesser extent). During the Napoleonic wars, Britain had fairly clearly gained the upper hand and had taken most of the desirable colonies. With the end of the war, France wasn't really in a position to try to take them back, nor did it (temporarily) have the willpower for further conflict.

For a short time afterward, Britain and France both had their hands full just trying to keep hold of their current possessions, France particularly since it was also trying to rebuild at home, but Britain had her own problems... rapid expansion is easy, keeping hold of those possessions isn't. The fact that Austria, Russia, Prussia (soon to be Germany), Spain, The Netherlands and the United Kingdom were all "keeping an eye on" France also meant that France, by necessity, had to maintain a fairly cautious foreign policy.

Fast Forward around 50 years, though, and although there were a couple of "Ooh, this is getting a bit tense" moments as France started to flex her muscles again, France and Britain were both fairly happy with their lot and far more concerned with trade than expansion. Both had recognised that they had little to gain from war, and shared many of the same interests. However, both were starting to become concerned about Russia and China, particularly, and the balance of power in Europe.

Next, we have some "Alliances of convenience" - The Second Opium War and perhaps more crucially the Crimean War, where France and Britain's interests aligned closely. It was in both of their interest to deal with these "situations", so they did. These joint-expeditions paved the way for closer ties.

Another 20 years, and we can see that Britain and France are sharing even more concerns: America is first embroiled in civil war (with a major impact on export to Europe, particularly the food from the Union France needs, and the Cotton from the Confederacy to feed Britain's textile industry). And after the Civil War America starts growing in confidence and starting to look outward, beyond her own borders.

Then Germany, already acknowledged (as Prussia) as having a strong military tradition ("Where some states have an army, the Prussian Army has a state!" - Voltaire), starts to expand. German Unification, and its closer ties with Austria, start to throw European politics out of balance. France and Britain had been fairly effectively keeping each other in check for some time, and actually hadn't been heavily involved ON the continent for nearly a century... but suddenly Germany was starting to look threatening. Militarily to France, exerting influence over regions that had "looked to" France for guidance, and obviously by sheer proximity, and threatening to Britain's burgeoning economy. Both were (rightly) fearful that Germany's increasing strength would lead to conflict, and their alliance was borne out of that.

And, essentially, that is how France and Britain became allies: through realizing that they had little to gain from war, were fairly well balanced, were threatened by the same (potential) enemies, and had mutual interests. There's a lot more to it than this, however, if you're interested in really getting into it.


In german history lessons (as I remember them) the main reasons are listed like this:

  • Great Britain had a policy called "two force standard" for its military fleet, which means GB's fleet should be not only the strongest but as strong as the second and third. Germany increased military ship production in a way that threatened to make this policy impossible to uphold. Consequently GB politics felt Germany was preparing to wage war against GB and had to be stopped before the two force standard was met no longer.
  • The foreign policy of Germany had changed. Earlier it was defined by Bismarck as "Germany is saturated" (meaning Germany is not interested in colonies, since German Unification after the Franco-Prussion war). Later Bismarck fell out of favor at the Prussian royal court and his policies were inverted:
    • Alliance with GB and Russia was discontinued (Germany willingly let the time-limit in some treaties pass although the treaties were originally designed to be extended in time)
    • Increase in military ship production (see above: "two force standard")
    • Late participation in the race for colonies in africa (this made the military ships "required" and was thus a triple provocation for GB: revoking the earlier stated "saturation" implies unreliability of statements, increase of military ship production implies aggression, participation in the race for colonies implies rivalry)

I'll allow myself a personal side note: I think Bismarck was right in choosing allies and pacifying them by not taking part in the race for colonies. In contrast, the German King Wilhelm II was an idiot for not seeing the intricate plans of Bismarck and the necessity of allies and peaceful foreign policy. It was under King Willi (as I like to call him rather unflatteringly) that Bismarck and his policies fell out of favor.

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    In support of the first point, spy stories in Britain were focussing on German power as a future threat - "The Riddle of the Sands" (Erskine Childers, 1901) a sailing holiday in Ostfriesland uncovers plans for an invasion across the North Sea. Commented Jan 14, 2015 at 15:26
  • With regards to your personal side note, it's hard to really tell which was cause and which was effect. Due to geography, Germany needed to balance France, Austria-Hungary, and Russia. An alliance with France was pretty much impossible. With the German / Russian relationships deteriorating -- in no small part due to conflict of interest between Russia and Austria-Hungary on the Balkans and French efforts to get closer with Russia, at some point it stopped being about Germany "being saturated" and Germany being threatened by a Franco - Russian pincer (with Britain interdicting the seas).
    – DevSolar
    Commented Jan 15, 2015 at 9:47
  • So at some point Germany dropped its game of alliances and balances, and adopted a stance of strength, focussing on its remaining ally (Austria-Hungary) to the detriment of relationships with other European neighbours. You could argue that they should have made concessions instead to avoid conflict, but you could argue as well that this would have put Germany in a very weak and vulnerable position between very strong neighbours, at least one of which held a definite grudge...
    – DevSolar
    Commented Jan 15, 2015 at 9:52

The Fashoda Incident was the culmination of Britain's North-South expansion through Africa colliding with France's East-West expansion. As Germany was increasing its dominance in Europe, England had to grab a major ally in Europe and their choices were either Germany or France.

The Boer wars largely arose from Britain's mismanagement in Africa and since France had a much greater African presence than Germany, that probably prompted them to side with France.

After the Fashoda Incident, Britain and France set out on a path towards much closer friendship.


Britain tended to ally with the second strongest country on the Continent against the FIRST. This was often for balance of power reasons. For many of those "close to 1000 years," France (with the best climate and largest population in western Europe) was the strongest country, and the greatest threat to Britain, and Britain would ally with others (e.g. small German states) against her.

But after the Franco-Prussian War, the defeat of France, and the unification of Germany, Germany became the strongest Continental power (and a very aggressive one), France second, and Britain allied with the second (France) against the first (Germany).

Under the circumstances, the change of alliances was not surprising. As Lord Palmerston would say, "We have no eternal alliances and no perpetual enemies. Only our interests are eternal and perpetual."

  • 1
    While this has some merit over a short period, it has no real longevity. It did not occur when Spain was the strongest, nor Holland-Belgium, and arguably Prussia was as strong or stronger than France during some periods (albeit worse led much of that time). It's true that Britain generally tried to maintain the balance of power on the continent, but she was more concerned with her own interests and almost always simply allied with the enemies of her OWN strongest competitor in trade and colonization.
    – Jon Story
    Commented Jan 13, 2015 at 15:22
  • @JonStory: Semaphore demonstrated that Britain allied with France against Spain several times. There was also a "reversal of alliances" Britain-Austria vs. France and Prussia in the 1740s, and vice-versa in the 1750s. Not to say that Britain did this every single time; only that this was her tendency. So Britain wouldn't necessarily ally with others against an "arguably" stronger Prussia or Spain, but mainly against a "clear and present" danger.
    – Tom Au
    Commented Jan 13, 2015 at 15:42
  • 1
    It did, but not because Spain was stronger - we need to be careful not to apply causality to circumstance. Britain tended to ally with the second, but purely for self-interest, not for Balance of Power reasons. A proportion of that self-interest was interest in the balance of power, but the main interest was simply that the most powerful was the biggest threat. I'll grant that they're related, but not dependent.
    – Jon Story
    Commented Jan 13, 2015 at 15:47

Enmity between Spain and Great Britain started when new royal family started in Spain. Until the Catholic kings Ferdinand and Isabella decided to join to the Austrian family marrying theirs sons Spain was only interested to fight against Islam. That provoked the union of families and also with the Austrian conservative ideology.

For this Spanish Austrian family the principal European enemy was France apart from the Muslim world. As long as the UK was pro-Austrian and against France, the alliance and friendship was total. However, with the arrival of the breakdown the Christian religion that alliance was broken.

Between XVI-XVIII century Europe was divided between two powers: The Austrian-German Alliance and the French Empire. UK joined France until the schism in the German-Austrian Empire that weakened the Austrian Conservative family. In XVIII, Austrian Family lost Spain. For the European great powers, Austrian power was destroyed. Becoming French and UK as the only big powers of Europe.

In early XIX.century, with Napoleon defeated, UK was the only giant of Europe while the rest of Europe countries were extremely weak. All countries of europe, decided to start the industrial revolution but with two visions: Protectionism (the resurrected Germany) or Liberalism(UK). France decided for UK and liberalism, Austria with Germany and protectionism.

Spain was divided, weak and in civil war until the Second half of XIX, joining with Liberalism of UK signed an agreement in 1906 with Alfonso XIII. That provoked the economic growth of Spain. Train, textile industry, electricity, shipbuilding, car industry, aircraft industry etc... until September 1923 with the withdrawal of British investments. With the Primo de Rivera dictatorship between 1923-1929, Spain chose the protectionism but decided to maintain relationship with allies necessary to win Rif War. Spain's pro-German or pro-UK attitude varied depending on the political situation.


Britain had not been involved in the outbreak of WWI, as Britain had no alliances that could force them to enter the war. If Britain actually entered the war was not in favor of France but in favor of themselves.

The main reason of Britain to enter the war was to protect their vast global empire from being affected by the war. Additionally, Britain saw the potential defeat of France as a very negative outcome for their maritime control, if Germany would eventually control the havens of the North Sea and the English Channel.

  • This is not strictly true. BBC History magazine did a special issue on the start of WWI on the anniversary. There were treaty obligations and internal political obligations.
    – MCW
    Commented May 20, 2016 at 16:22
  • Austrian TREASURE.... Commented May 20, 2016 at 19:26

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