Historians have long debated how and why the British were able to amass such a formidable and expansive empire in the years since 1497. And why were the British able to supplant the Portugese, Dutch and Spanish Empires in the Seventeenth and eighteenth Centuries and effectively see off French, Russian and German challenges over the nineteenth and early twentieth Centuries? These debates still rage and there is no definitive answer. For students, I have put a wider range of factors on the Student Zone brainstorm boards but some of the more commonly stated reasons are explained below.
Christianity, Commerce and Civilisation
This was a popular combination of factors given for the rise of the British Empire in the late nineteenth and early twentieth Centuries. The Protestant aspect of Christianity was seen by many within the British Empire as part of the larger battle with the more 'Catholic' nations of Continental Europe. Ever since the Reformation, religion represented not merely a spiritual difference between the Catholic and Protestant churches but was part of a far larger cultural and political competition between deadly rivals. Portugal, Spain and France were the Catholic nations who developed successful commercial empires before the English (and Dutch) were able to do so. Religion gave an excuse for this commercial rivalry to turn into military and political competition. The very success of the Protestant nations in challenging the Catholic hegemony in the New World and the East Indies seemed to confirm that God might be on the Protestants' side after all - although this did ignore the fact that the English and Dutch co-religionists were just as frequently found at the throats of one another.
It was certainly helpful that the Protestant work ethic meant that Christian and commercial ideals could be reconciled fairly easily and in fact was thought to manifest itself in the improvement and development of British civilisation in general. In pre-industrial Britain, the combination of the these three factors would lead to the creation of the settler colonies in North America. Devout Christians would look for economic freedom from feudal relationships in this New World. However, mercantalism and then the industrial revolution meant that this commercial aspect could take on a more sinister role as monopoly power, slavery or exploitative working conditions became a temptation hard for investors or capitalists to resist. It was reassuring to many such capitalists that they could hide behind the idea that by investing in enterprises and schemes around the world that they were serving a modernising and civilising goal and so their consciences could be clear in such a noble enterprise.
The civilisation aspiration could be damaging in its own right. It assumed that British civilisation was innately superior to those it was subjugating. Indeed, the very subjugation process confirmed the superiority of British civilisation! It then assumed that the new rulers were obliged to improve the subjugated peoples that it had taken under its wing with large doses of Christianity and commerce. Of course, this appealed to the positive aspirations that many Imperialists held for the future of a benign Empire. It offered a justification for Imperialism. However, it could also justify some of the more extreme Social Darwinist ideas of racial superiority and it allowed for treating the subject peoples as innately inferior.
In summary, Christianity, commerce and civilisation was a neat way to justify the uniqueness of the British Empire and yet give it a justification for continuing it into the future. It could also be deeply patronising and justified cultural imperialism and racial stereotyping and yet there was a surprisingly large dose of truth behind these motivations and strain of British imperialism.
Mercantilism and chartered monopolycompanies were becoming quite the fashion in the late sixteenth and seventeenth centuries (and would live on to the nineteenth in some cases. It was a cheap and relatively easy way for a feudal monarch to gain an income on the back of his nation's prestige and maritime exploits. He (or she) could give permission to explorers to claim lands on his (or her) behalf and then authorise certain companies (with the aid of Charters) to exploit the natural resources in that part of the world in return for a fixed income to the monarch. In many ways it was something for nothing for the ruler. He could provide exclusive (monopoly) rights to certain cronies in return for money, political support or promotion at home. It invariably, but not always, resulted in ignoring the rights of any indigenous or local peoples that were 'in the way'. If the political entity was too large and powerful then alliances might be entered into or the monarch might lend the company the support of his nation's military wings. The Spanish and Portugese long used this system of government, and the French and Dutch followed suit. It was to be no surprise that England (then Britain) would also follow this model - at least for a while. The Stuart monarchs were particularly keen on this economic model - especially as it seemed to provide the permanently cash-strapped Stuarts with much needed money. Over time though, problems did arise. Companies were often more interested in making a profit than in taking care of the people it ruled over. When rebellions or riots broke out, it was invariably the government who had to come to the rescue as the company's resources would be quickly depleted by long, drawn out and expensive campaigns. The famous 'East India Company' had to go cap in hand to the British Government to save it from bankruptcy but not before many individual investors and directors had made fortunes. They would sell their shares when it looked like trouble was looming - it was the small or institutional shareholders who invariably got caught out - or the British taxpayer!
Slavery would show just how exploitative and morally bankrupt this system could descend to. Plantations needed labour and labour was available, relatively cheaply, in West Africa. It was when slaves started revolting and rising up in rebellions that questions were asked back in Britain - why precisely was the government spending money and resources supporting slave owners against slaves? They had not shared the profits in the 'good' years, why should British taxpayers support them now that they were suffering? Surely it was their own problem? Non-conformist Christians in particular found it easier to challenge the status quo of slavery when their moral arguments were joined by these no less tricky economic ones.
Technological and Industrial Superiority
The British had no monopoly on technological innovation. Gunpowder, the printing press, navigational equipment were all developed and improved on the continent or further afield yet. Europe from the fifteenth century onwards was becoming a dynamic place where new ideas were swirling around with unnatural haste. Britain was benefitting from this much wider European Renaissance and Age of Enlightenment and yet it was also in a position to take these ideas, and many others, much further as it would become the first nation to harness the power of steam which in turn would unleash an Industrial Revolution and an avalanche of high quality, mass-produced goods that would flood markets all around the world. They, in turn, would provide a technology gap that non-European nations would find difficult to compete with. Precision-made muskets, rifles, machine guns, train locomotives, steam ships would provide the relatively small and over-stretched British armed forces with unparalleled advantages. They could take on vastly larger (and possibly braver) enemies and yet beat them off, subdue and suppress them. British weaponry was very effective and its communication systems allowed it to shepherd its meagre resources to devastating effect and even its medical resources would improve enough to allow its soldiers and sailors to penetrate deeper and more inaccessible areas. Britain was not the only nation to enjoy a technological advantage over non-European nations, but its combination of industrial might, commercial prowess and maritime power meant that it had a peculiar advantage and one that would not be challenged until the development of guerilla warfare and tactics in the Twentieth Century.
Sir John Seeley once stated that the British Empire was acquired in a 'fit of absent-mindedness'. What he meant by this was that the Empire was acquired for a variety of reasons that did not add up to a coherent whole.
He also had in mind the fact that new colonies were being added in order to defend existing colonies and borders. The best example of this might be the colony of India. It was certainly regarded as the Jewel in the Crown of the British Empire but it also meant that a surprising number of supporting colonies would be added to guard the so-called 'Jewel' itself or the routes to and from the Jewel. For example, the British were keen to take control of the Cape Colony from the Dutch during the Napoleonic Wars to secure the main sea route to India. Likewise, islands like St. Helena, Mauritius and the coastline of Aden were all added for similar reasons. Of course, when the Suez Canal was opened in the 1869, it was not long before the British took a controlling interest in the Suez Canal Company and soon became involved in controlling the Egyptian administration itself as this new route to Asia displaced the Cape of Good Hope route. Then, once Egypt was a colony, Sudan and Cyprus became part of the Empire. Even within India itself, British control was expanded from coastal factories to dominate the interior and then becoming involved in acquiring the Himalaya region to defend the approaches to India. There was a relentless logic to guarding the next valley, river or island that soon got the British involved in places that had little strategic importance except to the colonies that it already controlled.
The Royal Navy would undoubtedly become a formidable military institution, but it was not always inevitable that Britannia would rule the waves. Naturally, being an island nation, ship-building and sailing would be important skills and industries to a country like England. But, Portugal and then Spain had got off to a far more promising start with regards to maritime domination of the seas from the fifteenth century onwards. They had come to understand the ship design, navigational and long distance skills required to explore and commercially exploit the routes that they discovered. The English were always playing catch up or were merely picking up the scraps left by the Portugese and Spanish. If anything, it was the Dutch and French who first challenged Portugese and Spanish control of the seas. This situation would not really be transformed until the Eighteenth Century. The Glorious Revolution of 1688 where the Dutch King William of Orange took control of the English Crown would reduce, but not remove, Anglo-Dutch rivalry. However, it would not be until the Seven Years War of 1756 to 1763 that the Royal Navy would take on the far richer and supposedly more powerful Kingdom of France. This was also something of a legacy of the Glorious Revolution in that the Dutch brought sophisticated banking techniques (including the formation of the Bank of England) that would allow the British to borrow money to build a huge Navy. The idea of this investment was to pay back the loans once Britain had been victorious in the war. The French Navy had no such infusion of investment and so they were hard pressed to see off the challenge from the Royal Navy especially on the global scale of what was really the first 'World War' in that it stretched over all corners of the globe. In some ways, the French were able to get an element of revenge by helping the American Revolutionaries in the 1770s and 1780s in their humiliation of the British. But this in itself would be a false dawn for the French Monarchy. They had invested huge quantities of money to challenge the Royal Navy (and help the Americans to win the Revolutionary War) but without the benefit of receiving tangible assets to recoup this investment.
It is not an understatement to say that one of the prime reasons for France's own Revolution was because their cupboard was bare after helping the American Revolutionaries. This of course would lead indirectly to the Napoleonic struggles between France and Britain. Napoleon would concentrate on his land campaigns, but he would be constantly frustrated or harassed by the Royal Navy. For example, Nelson destroyed Napoleon's fleet at anchor off Egypt in 1798 which killed off his Pyramid Campaign. Napoleon would try to combine the French and Spanish fleets to lure the Royal Navy across the Atlantic to allow him to launch an invasion force against England. The resulting battle of Trafalgar in 1805 became the defining naval battle for the next century. The British did not fall for the lure and ended up blockading the French and Spanish fleets instead. Once these fleets set sail, Nelson directed an aggressive assault that would destroy them and leave the Royal Navy ruling the waves until World War One and beyond. For the rest of the Nineteenth Century, there was no maritime power who could come close to challenging British domination of the maritime communication and trade routes. This meant that the British could hoover up all the outlying French, Spanish and Dutch colonies in the remainder of the Napoleonic Wars and could then guarantee the safety of all of these isolated and far flung outposts from at least maritime threats. Britannia really would rule the waves and this undoubtedly made imperialism easier to implement and international trade to thrive which also aided the industrialising Britain.
Marxist/Leninist Stages of Development
One interesting theory to explain Imperialism was borne out of the works of Karl Marx. In fact, it is more due to Lenin's adaptations to Marx's writings that colonialism was brought into the fold, but it relied on the historical determinism put forward by Marx. Basically, he believed that human societies were travelling through economic stages of development before reaching the Communist Utopia where all are treated equally and all goods are distributed equitably. Feudalism was a pre-condition for Capitalism which in turn was a pre-condition for Communism. It was argued that Capitalism had the seeds of destruction within itself - capitalists would compete with one another as they strived to make more and more profit - but they would be reduced in number but becoming more efficient simultaneously. Eventually, it would be so efficient that it would produce all the worldly goods that consumers would desire, but there would be so few capitalists left that the wage slave workers (who were becoming more and more exploited) would rise up and seize the factories and the means of production. It was Lenin who had to adapt this theory to why a revolution might take place in relatively non-capitalist Tsarist Russia which was barely moving out of the Feudal phase. He basically added another layer of inevitability to explain that capitalist Europe was competing for the raw materials and markets that colonies could provide. It was this, he explained, that would result in the outbreak of World War One, as European nations desperately competed with one another for colonies and once these ran out, would fight one another for domination - bringing the day forward for the 'real' Communist Revolution. He therefore advocated staying neutral in the Capitalist war but was not averse to taking the opportunity to seize power in October, 1917 as Russia was worn out by the long drawn out attritional, total war.
Communism was an easy ideology to sell to poor, exploited and oppressed peoples around the world, Communist organisations and groups therefore became major resisters and opponents to Imperial regimes the world over - especially when they became tied to Cold War politics. Unfortunately, when agricultural or primary resource colonies gained their freedoms with the promises of a Communist Utopia to fulfil it did not take long for disappointment, cronyism and corruption to undermine and discredit Communism as a viable form of government. It may have given some people inspiration to remove their imperial overlords, it just could not deliver on its promises.
Another interesting theory was one proposed by two economic historians, Gallagher and Robinson, who basically stated that the British Empire actually tried not to take colonies if at all possible. In fact, colonies were almost a sign of failure. They argued that the British were interested in trade opportunities and if they could gain access to markets and raw materials without the need for colonising then so much the better. They gave examples of British 'soft' power existing in the Americas, China and the Mediterranean area. These were areas where the British could do business but without the overheads and costs of administering and defending territory. The argument explained the late Nineteenth Century surge in acquisitions in being a consequence of having to respond to the aggressive competition with other European powers who were keen to take the lands, markets and resources for themselves and deny them to rivals as the world seemed to turn to protectionism. Even Britain itself was tempted by the Imperial preferences proposed by Chamberlain at the beginning of the 20th century. This theory would radically redraw the imperial map giving precedence to those areas where no formal British control was required at all.
One theory for Britain's domination of the large slices of the world was described as Britain being able to have taken in the resources of the various colonies in form of goods, capital, science and populations and then reallocated them more efficiently using the institutions and condensed political power available in the mother country (the Metropole) and especially those in London. This theory is based on the idea of the strong central government, educational, commercial and financial institutions which mutually reinforced one another and used the resources of the empire to further enrich themselves and build up an ever stronger competitive advantage - economically, strategically and politically. It believed that the institutions used their wealth and power to guard their positions of power and to further their own interests using the Empire as a conduit or arena in which to exercise their talents and power. In this model, the periphery colonies were at the tender mercies of the dominant metropole and had little local control over their destinies but had merely to respond to orders and directions from the centre.
Complex Patchwork of Interacting and Dynamic Agencies
Coming somewhat full circle in the debate is the idea that the Empire was a far more complex, ad hoc collection of competing, dynamic collection of agencies, individuals and companies which had no set agenda but found the Empire a convenient arena in which to forward their own interests. Unlike the Metropole example above, this theory believed that the actors could literally come from all over the globe, including native peoples or their rulers and had no fixed example of what the Empire should be like. This theory sees the variety of colonial governments, forms and institutions as evidence of a far more haphazard but flexible approach to the concept of what constituted empire. Some actors were happy to remain on the fringes of a free trade empire, others lobbied for inclusion in a far more centralised form of administration. Some wished to benefit from the protection that the Empire could provide, others used the colonial experience only so long as it was useful to their ends and then jettisoned it when it had outlived its purpose. This theory believes that the empire was a complex intermingling of motives, attitudes and purposes. It also believes that the localisation of these concerns means that a much more nuanced appraisal of Empire is possible as successes and failures can be itemised and broken up regionally and by era. Empire was useful to some groups or colonies at some points in time but exploitative or damaging at others. Using this theory, it is less a zero-sum game of saying that Empire was a 'good' or 'bad' thing as in some other theories.
Combination of Factors
Of course, there is rarely a single answer to the complicated realities of politics, economics and military rivalry. There is probably no single reason to explain how Britain created such a vast institution. Various isolated reasons, advantages and localised situations would combine to create a series of justifications for seizing isolated colonies that combined to form the huge and expansive British Empire.
Historians have debated the motivations and justifications for these processes for pretty much as long as their has been an empire itself! If you would like to follow the historiography and debates on the the British Empire over the years please take a look at the Library section.