The Qing Empire’s military drew from the traditions of bodyguards and booty warfare in North-East Asia (primarily what is now southern Jilin province) in the late sixteenth century. The foundations of imperial expansion were built during the long war with Ming China, from 1618 to 1644, which allowed the Qing to absorb the central features of Ming military technology. Patterns of human management and technology application established in this period persisted over the next forty years as the Qing completed their conquest of China and Taiwan. After 1685, Qing expansion spread out to Mongolia, Qinghai, Tibet, and what is now the province of Xinjiang. These wars, against less densely populated, sometimes nomadic zones, changed Qing campaigns significantly. By the nineteenth century, the century and a half of focus on the continental frontiers left the Qing poorly prepared for seaborne challenges, and from some technologies that the Qing had previously regarded as less relevant to their military needs.

The Japanese archipelago and the Korean peninsula are neighbouring regions, with histories of similarities and contrasts. Currently inhabited by a population of about 123 million in an area slightly bigger than Germany, Japan has been relatively isolated throughout much of the last two millennia. In the late nineteenth century, Japan reinvented itself from a land on the margins of the Sinitic cultural zone to a world power. In contrast, Korea – a landmass a little larger than Great Britain and inhabited by about 78 million people – was an active participant in the China-centred world order during much of its 2,300 year-history before losing sovereignty to Imperial Japan in 1910. (See Map 13.)

For almost three millennia the pastoral nomads of the Eurasian steppe formed a great reserve of mounted cavalry, threatening their settled neighbours while offering them goods and services of great value – in particular horses and skilled soldiers for their armies. The Eurasian nomads were also empire-builders, creators of imperial ideology and administrative structures that were passed down through generations of successor states. Their imperial centre in Mongolia was home to two related peoples – the Turks and the Mongols – each defined by the powerful empires they erected. The Türk Empire, which flourished from the mid-sixth to mid-eighth centuries, was the first of these and it controlled the steppe from Mongolia to the Volga river, fighting and trading with China, the empires of the Middle East, and Byzantium. The second great state was the Mongol Empire, founded by Chinggis Khan in 1206. The Mongols extended their power yet further than the Turks, conquering much of Eurasia.

Generations of historians have seen the interplay between the early modern state and its armed forces, and between warfare and state formation, as key factors in the process of modernisation. The creation of the modern state was most powerfully expressed through the supposed symbiosis between absolute regimes and standing armies. The image of geometric order and discipline generated by formations of infantry drawn up in kilometre-long battle lines; the authorities’ direct involvement in provisioning, equipping, and uniforming its soldiers; central government’s reach into every aspect of warfare and military planning. All of these have been regarded as defining traits of the interconnection between the standing army and the state. Research on the inner structures of early modern military society has, until recently, been coloured by preconceptions about functioning hierarchies and chains of command, an increasingly effective military administration, rigid discipline, and corresponding efficiency in the waging of warfare. Such a top-down view remained unchallenged as long as researchers relied almost exclusively on sources derived from governmental and/or legal provenance, leaving an impression of overwhelming state authority reaching right down to the level of the common soldier.

The four volumes of the Cambridge History of War were conceived in global terms. The aim was to go beyond a history centred on warfare in Europe, in which the global context emerged solely through the eyes of European exploration, trading, and colonisation. Instead, the volumes would seek to provide the reader with a broader approach to warfare across the world, in which the experiences and trajectories of states and their military systems could be examined and compared. Europe and Europe’s military engagement with the wider world would have a place, but would not be the single point of reference from which global warfare would be seen. This aim was the starting point for Volume III, both as initially conceived by the first editors, John Childs and Arthur Waldron, and then by the current editorial team.

‘Bella gerant alii.’ In 1516, by means of traditional dynastic finagling, the house of Habsburg acquired the thrones of Castile and Aragon, or Spain for short: the most bellicose and spectacularly expanding state in Latin Christendom. Henceforth, it seemed, the Habsburgs would no longer be able to leave war to others.

Since concluding Castile’s civil conflicts in the 1470s, the Spanish monarchs had, by force of arms, reconquered parts of French Catalonia, and added other acquisitions to their realms: southern Navarre, the western Canary Islands, Melilla, much of the Caribbean, and the kingdoms of Granada and Naples. For what came to be known as the Spanish monarchy it was the start of the most sustained period of success – measured by the crude, but decisive, standards of victory in the field and expansion on the frontiers – any Western European state had achieved since the Roman Empire.

The siege played such a dominant role in both medieval and early modern warfare that it is difficult to overstate the significance of the twin revolutions in gunpowder artillery and fortification which together transformed fortress warfare and the face of Europe. The continent was to be marked by chains of new frontier and coastal forts, expanded naval bases, and girdles of earth-filled ramparts and bastions around towns, often sweeping away picturesque medieval walls and towers and replacing them by much lower-profile works. The rash of urban citadels by which so many rulers sought to guarantee their security would be matched by what Parker called the ‘demilitarised zone’ of central France following the Wars of Religion and the Fronde. Ruined fortresses litter the continent. The demolitions following most civil wars, rebellions, or frontier adjustments speak to the importance of fortified places. Whether it was the local power projected by castle or border fort or the major concentration of resources protected by walled towns or major fortresses, fortified places were the main objective of offensive operations.

For all of the obvious importance of warfare in the period when the Safavid dynasty (1501–1736) was in power in Iran, relatively little has been written on the topic of the military in this formative phase of Iranian history. Jamil Quzanlu, Vladimir Minorsky, and Laurence Lockhart were the first to address the organisation and development of the army in the Safavid period. Their studies have since been supplemented by the work of Yahya Dhuka, Khanbaba Bayani, Masashi Haneda, Richard Tapper, Willem Floor, Walter Posch, Giorgio Rota, and the present author. Much work remains to be done, though, and what follows is therefore a preliminary survey.

Sea power, classically defined as a strategy to control communications, was an essential asset for the creation of European maritime empires, enabling them to secure seaborne trade, open new markets, and acquire territory. It has often been conflated with seapower, a concept developed by the ancient Athenians to distinguish states like their own, whose economy, culture, and identity were enmeshed in the maritime sphere, from continental military powers like Sparta and Persia. In this period Britain, the only seapower Great Power, created an extensive maritime empire outside Europe, one combining colonies of settlement, like Australia, with those of occupation, and informal imperialism based on economic power. While many Continental European powers created maritime empires after 1815, they did so in the knowledge that their possessions would be exposed to British naval power in the event of war, and tended to focus on land and security rather than commerce.

Naval warfare changed out of all recognition from the late sixteenth century onwards through the rapid development of large square-rigged warships carrying heavy broadside gun batteries. A whole series of developments followed, with a long (if far from smooth) evolution in ships, equipment, strategy, and tactics continuing down to the last sailing navies of the early nineteenth century. It was clearly no accident that this naval revolution coincided with a great age of global European empires, which would have been impossible to create or maintain without effective naval power. Galleys and other oared craft became largely obsolete, except for some amphibious operations in the Mediterranean and for use in shallow waters around the innumerable Baltic islands. The crushing Dutch victory over a Spanish fleet at the battle of the Downs (1639) marked the first occasion when the full power of broadside gunnery became evident. Then the three Anglo-Dutch wars between the 1650s and 1670s saw a series of savage and bloody engagements between the fleets of two nations that were coming to be known as the Maritime Powers. The combination of imperial and trading ambitions, new financial arrangements, and relatively open societies enabled first the Dutch, and then the British, to develop naval power to new heights, in turn allowing them to punch well above their weight on the international stage. Under Louis XIV, France did mount a serious challenge to the Dutch and English, and for a time possessed the largest navy in the Western world. However, by the 1690s the French, and more gradually the Dutch, were finding the costs of maintaining this level of power at sea, as well as on land, to be too great.

Discontent in Britain’s Thirteen Colonies had built to open violence by the mid-1770s, much of it occurring in and around Boston. (See Map 19.) A lack of representation and perceptions that British leaders pursued overbearing policies because they were indifferent or even hostile to the plight of the inhabitants pushed ever more colonists towards open rebellion. In response, the tools Britain possessed to confront its colonial troubles were limited by the nature of its government and the few instruments at its disposal. These included the army and navy, but their use at Boston only exacerbated tensions. Fighting flared on 19 April 1775 when British soldiers attempted to seize munitions at Concord, Massachusetts. Along the way, at Lexington, shots were fired and several colonists were killed. Afterwards, colonists sniped at and harried the British on their return to Boston. In the wake of Lexington and Concord, American militia gathered around Boston, surrounding its British garrison. Nearly two months after the outbreak of hostilities, the Americans seized and fortified the strategic Charlestown Peninsula overlooking Boston harbour. In response, the British stormed the position in what became known as the battle of Bunker Hill: the first major battle of the American Revolution. At the end of the day, the British held the field, but at the cost of nearly a quarter of their army in Boston.

Sub-Saharan Africa was on the threshold of a new and violent era in the second half of the fifteenth century. The ensuing four centuries would see innovative forms of military organisation, novel cultures of militarism underpinning such systems, and new wars, as well as new ways of fighting them. There were often different factors at work in different regions; the presence of external drivers was a key distinction between Atlantic Africa and the rest of the continent, for instance. However, warfare across early modern Africa had much in common, in terms of the aim to control factor endowments, to maximise population, and to construct enduring ideological systems, whether territorially or culturally defined. In some ways – certainly in terms of the underlying trends and broad contours of Africa’s military history – the existence or absence of external intrusion is a distraction, however significant it was in particular places at particular times. The outcome of the processes in motion between c. 1450 and c. 1850 was an expansion in military scale, the professionalisation of soldiery, the adoption of new weaponry, and the militarisation of the polity – whether ‘state-based’ or otherwise. The militarisation of African polities and societies was an ongoing process between the fifteenth and the nineteenth century, a period which in many ways witnessed the laying of the foundations of modern African political systems; this would culminate in a veritable military revolution in the nineteenth century, a transformation in the organisation and culture of violence, without which Europe’s later partition of the continent cannot properly be understood.

The nineteenth-century Russian poet Fedor Tiutchev rightly marvelled at his motherland’s remarkable growth: ‘Moscow, and Peter’s town, and Constantine’s city, these are the Russian realm’s cherished capitals … But where is its limit? Where are its borders? The fates will reveal them in times to come …’ Over the past 400 years an obscure principality deep in the forests on Europe’s eastern edge had expanded to become the largest continental empire on Earth – a domain whose immense territory stretched from the Baltic Sea to the Pacific Ocean and beyond, covering one-sixth of the planet’s dry surface. Although somewhat diminished in size after the collapse of the Soviet Union in 1991, Russians today still nickname their country ‘the seventh continent’.