held that nations were bound by unwritten laws common to all mankind and rooted in human nature.23 As written in Justinian’s Institutes, a widely glossed sixth-century compilation of Roman law, “the law which natural reason has established among all mankind and which is equally observed among all peoples, is called the Law of Nations, as being that which all nations make use of.”24 The law of nations held that certain practices were shared by all peoples, that these practices were rational and natural, and that they offered a customary or normalized way of dealing with foreigners and strangers, even those who were pagans or heretics.25 Throughout the sixteenth century, the law of nations saw wide adoption as European princes sought to define their imperium, or rule, and dominium, or territorial possessions, in relation to other sovereigns. In the late sixteenth century, many European jurists claimed acceptance of the law of nations as an international legal system. The English crown, in particular, encouraged the study of Roman law as a way to legitimate its power at home and abroad.26
Particularly salient for the English crown were Roman criteria for defining legal possession of terra incognita, or undiscovered territory, a topic about which the common law offered no guidance.27 As codified by Justinian, Roman law specified that land must be brought under control for possession to hold. Valid title demanded more than animus, or future plans to settle. As Justinian’s Digest put it, “we cannot acquire possession solely by intention.”28 Legitimate title also required corpus, or physical possession. This criterion gave the English a powerful rhetorical lever in negotiations with Spanish crowns. While the Spanish had claimed the American landmass since the fifteenth century, they had settled only as far north as present-day Florida, leaving northern latitudes theoretically open for the taking. Throughout the late sixteenth and early seventeenth centuries, English colonists frequently made claims to the North American coast, asserting that unoccupied land was the property of the first Christian prince to settle it.29 Just as often, however, English claims included territories that, far from being empty, were heavily populated and defended by Native polities. To claim control of such territories demanded justifications that described the conquest of occupied territory.30 Many scholars of colonial law have associated conquest almost exclusively with New Spain and the infamous Requerimiento. They have argued that the English established New World claims by building fences and fortifications rather than by conquering people.31 This is true, if one defines conquest in military terms. English colonists almost never sought to incorporate Native people into their societies after defeating them in wars.32 However, the term conquest possessed a range of meanings in early modern England, many of which had little to do with military subjugation.33 While the English sometimes waged holy wars of the kind justified by the Requerimiento, they preferred to advertise New World conquest as a benevolent pursuit, involving the peaceful subjugation of land and peoples.
In this book, I will argue that treaties were part of the English strategy for carrying out a supposedly peaceful conquest. This may seem like a paradoxical claim. Today, we think of a treaty as an agreement between equal states, not a conquest of one party by another. Yet this is largely a modern view. Early modern princes frequently made treaties with inferiors, including vassals, feudal lords, and even rebellious subjects.34 These foedera vel inaequalia, or treaties between unequal parties, could involve many different matters, such as land rights, political loyalties, trade agreements, and even religious commitments. Unequal treaties were of particular interest to monarchs during the early period of colonial settlement, when the question of competing claims to overseas territory was increasingly becoming part of European treaty negotiations.35 Indeed, long before the English set their sights on New World settlement, Spanish monks had debated the legality of the Requerimiento, suggesting that Spain’s claims to the Indies violated the natural rights of the inhabitants. In a series of lectures printed throughout Europe, the Dominican friar Bartolomé de Las Casas argued that Indian treaties offered a means of conquering territory that was consistent with natural law.36 “Is it customary and right, in reason and natural law,” he asked in 1526, “to ask [the Indians] to swear obedience to a foreign king without establishing a treaty or contract or covenant with them regarding the good and just way in which the king would rule them?”37 Beginning around 1530, Francisco de Vitoria, a Dominican who taught at the School of Salamanca from 1527 until 1540, likewise argued that treaties offered a way to claim American lands.38 In a series of lectures later published by his students, Vitoria refuted the idea that the Spanish monarchy had power over the Indians in “temporal and civil matters,” such as the possession of territory.39 Vitoria argued instead that the world was governed by natural law, which held sway over all people, Christians and unbelievers alike. Postulating that “Any commonwealth can elect its own master,” he argued that the Spanish could claim dominion if “the barbarians recognized the wisdom and humanity of the Spaniards’ administration, and one and all, both masters and subjects, spontaneously decided to accept the king of Spain as their prince.”40 Vitoria viewed indigenous consent to Spanish rule as a theoretical source of title, as long as the treaty was made in the absence of “fear and ignorance” and therefore satisfied the criteria of consensus ad idem.41
The arguments of Las Casas, Vitoria, and other critics of the Requerimiento were never widely embraced by Spanish monarchs.42 However, starting in the late sixteenth century, many Protestant jurists adapted such ideas to the project of colonial justification. During the first decades of English colonization, Alberico Gentili, a professor of civil law at Oxford, published widely about the law of nations. His writings and frequent public lectures strongly influenced English colonial promoters and the royal councilors who lent financial and legal support to colonial endeavors.43 In 1589, he published De Jure Belli Libri Tres, an authoritative application of Roman texts to legal problems arising from war and colonization. In particular, Gentili addressed the problem of how refugees, exiles, or settlers from populous countries could lawfully acquire sparsely occupied land that was nevertheless claimed by another sovereign. Gentili argued that “because of that law of nature which abhors a vacuum, [such lands] will fall to the lot of those who take them.” However, he specified that the original sovereign would “retain jurisdiction over them.” In describing how such an arrangement might work, Gentili approvingly quoted Aeneas’s vow to Latinus during the Trojan invasion of Italy. “‘I do not ask for dominion. Let both nations [Italians and Trojans] unconquered form a union on equal terms and live under equal laws.’”44 The idea of a union between Christians and pagans was also put forward by Hugo Grotius, a Dutch jurist who published several widely read treatises on the law of nations. The work of Grotius did not circulate widely in England until settlement was well under way, but many colonial writers turned to his texts for support. Like Vitoria, Grotius addressed the question whether Christian powers could make agreements with unbelievers. “A question frequently raised concerning treaties,” he wrote, “is whether they are lawfully entered into with those who are strangers to the true religion.” Grotius held that “According to the law of nature” there is “in no degree a matter of doubt” about the lawfulness of such treaties. Grotius pointed to the contract between the Jews and the Egyptians as a biblical precedent for the lawfulness of treaties between believers and idolaters.45
At the same time that jurists were making arguments about Indian treaties, English sailors and travelers were putting such ideas into practice, largely as an anti-Spanish strategy. In 1572–1573, English privateers formed ad hoc military alliances with the cimarrónes, groups of freed slaves and Native people who had fled the Spanish.46 Sir Francis Drake and John Oxenham described the raids in letters that were widely read by English colonial promoters, such as Richard Hakluyt, who advised that colonists “have firme amitie” with neighboring indigenous peoples so as to become “strong in force” and better able to resist Indian or European enemies.47 Native treaties were also a way of giving an appearance of legality to overseas activities that the Spanish crown viewed as piracy. During a voyage to California in 1579, Drake reportedly sat down to feast with a king who gave him a crown and scepter while his people sang a song “with one consent, and with great reverence.”48 Drake completed this act
