From the Mediterranean coast of northern Spain to the island states of the South Pacific, secessionism is on the rise. In 1915, there were eight movements seeking their own independent state. In 2015, there were 59. One explanation for the increase is that there are now more countries from which to secede. But even taking that into account, the rate of secessionism has more than doubled over the last century.

Yet even though more groups are trying to break away, fewer are resorting to violence. Because secessionists wish to join the exclusive club of states, they pay close attention to signals sent by major countries and organizations that indicate how they should behave. So far, those signals have discouraged them from resorting to violence (and made them more careful to avoid civilian casualties if they do) or unilaterally declaring independence. Kurdish forces in Iraq and Syria, for example, have largely avoided killing civilians and have offered assistance to Western powers fighting the Islamic State (or ISIS). Somaliland, which broke away from Somalia in the early 1990s, has worked quietly but effectively with countries trying to curb piracy in the Gulf of Aden. And in Catalonia and Scotland, independence movements have long opted for referendums and negotiations rather than unilateral declarations.

This good behavior has gone largely unrewarded. Amid the war against ISIS, Turkey and the United States have moved swiftly to tamp down talk of an independent Kurdistan. No country has recognized Somaliland’s statehood. And the Spanish government declared Catalonia’s independence referendum illegal and ignored the result. Meanwhile, the newest member of the club of states, South Sudan, won international recognition despite flagrantly violating international law and human rights during its struggle for independence.

This contradiction presents secessionists with a dilemma: Should they believe what they are told is the best path to statehood or what they can see actually works? In recent decades, they seem to have closed their eyes to the gap between rhetoric and reality. But the ability of major countries and international organizations to maintain the fiction that good behavior leads to success may be eroding. 

If secessionists conclude that abiding by the rules generates few rewards, the consequences could be ugly. Some will continue to play nice for their movement’s own internal reasons. But those who see the rules as an external constraint will swiftly abandon them. That could send the recent trend of nonviolent secessionism into reverse and increase the human costs of war in places where secessionists have already resorted to rebellion. 


It is common for analysts of international affairs to note that since World War II, civil wars have become more frequent than wars between states. Less well known is the growing trend toward secessionism among rebel groups that fight in civil wars. Data I collected with my fellow political scientist Page Fortna show that the proportion of civil wars in which at least one rebel group aimed to secede rose from zero in 1899 to 50 percent in 1999. 

There are several reasons for this increase. First, the creation of the United Nations, in 1945, codified a norm against territorial conquest that is meant to protect all member states. Today, states worry less about being swallowed up by their neighbors than they used to. Second, other international organizations have created a set of economic benefits to statehood. Members of the International Monetary Fund (IMF) and the World Bank are eligible for loans and aid. Members of the World Trade Organization are afforded the benefits of lower trade barriers. And third, the principle of self-determination, which is crucial to the secessionist enterprise, enjoys more international support today than in previous eras.

But secessionists face an uphill battle. Existing states, international law, and international organizations have laid out several conditions for the recognition of new states. The 1934 Montevideo Convention, which set a standard for statehood on which countries continue to rely, lists four criteria: a permanent population, a defined territory, a government, and the capacity to enter into relations with other states. Those requirements might not seem to present many problems; several currently active secessionist groups could meet them. But the bar has risen significantly since 1934, especially after the main wave of decolonization ended in the late 1960s. 

Consider the United Kingdom’s policy on recognizing new states, which is typical of the policies of many Western democracies. If the leadership of an existing internationally recognized state is overthrown, British policy automatically grants the new government the same recognition as the old one. But gaining recognition as a new state—the project of secessionism—is a steeper climb. The British government requires that in addition to meeting the Montevideo criteria, would-be states must respect the UN Charter and the basic principles of international law, guarantee the rights of minorities, accept certain commitments regarding disarmament and regional stability, sign up to a raft of other human rights obligations, and not violate any UN resolutions. 

The United States takes a similar approach, at least on paper. U.S. policy adheres to the criteria laid out in the Montevideo Convention but admits the possibility of exceptions, such as to the requirement that a new state have clear territorial boundaries, if political expediency dictates. In practice, political factors often take precedence over principles. U.S. policymakers have on occasion expressed support for new states that have achieved quite limited progress toward effective governance and democracy.

Gaining UN membership is an even more explicitly political affair. The UN prefers that aspiring members first join their main regional organization, such as the African Union or the Organization of American States. Then a state must apply to the UN secretary-general’s office. The most viable applications will eventually be discussed, and perhaps voted on, by the UN Security Council, which must approve new members. Because any of the five permanent members of the council can veto an application, many applicants, including Kosovo, Palestine, and Taiwan, have been unable to achieve membership. 

Groups whose UN membership bids fail may nonetheless succeed in joining other international organizations or gaining recognition from other countries. Both Kosovo and Taiwan are members of FIFA, the international football organization, as well as their regional economic development banks. Palestine is recognized by 70 percent of the UN’s members and in 2012 was upgraded from a “non-member non-state” to a “non-member observer state” at the UN by a vote in the General Assembly.


Unlike groups that seek to overthrow the central government or plunder resources, secessionists require foreign recognition to achieve their goals. For that reason, what international organizations and major countries say about secessionism matters. The UN has expressed a clear preference against the use of violence by independence movements, and the evidence suggests that secessionists have listened. Even though secessionist movements account for an increasing proportion of rebel groups in civil wars, the percentage of all secessionists engaged in war has fallen. An increasing number of secessionist movements begin entirely peacefully, and other formerly violent secessionists have turned to nonviolence. Since 1949, secessionist movements have been half as likely to fight large-scale wars (those resulting in at least 1,000 fatalities) as they were in the previous century. 

Secessionists understand the political downsides of violating international humanitarian law.

Meanwhile, secessionist groups that have resorted to violence have moderated their conduct in war. Secessionists are over 40 percent less likely than nonsecessionist armed groups to target civilians in civil war. That is in part because secessionists understand the political downsides of violating international humanitarian law. Many secessionists make a special effort to broadcast their compliance with the laws of war. For example, several groups, including the Polisario Front (which seeks to end Moroccan control of Western Sahara), the Moro Islamic Liberation Front (an armed group in the Philippines), and the Kurdistan Workers’ Party in Turkey, have highlighted their commitment to avoiding the use of antipersonnel land mines. Secessionists have also contrasted their own behavior with that of their government opponents, who often resort to harsher tactics. 

Consider the little-known case of the South Moluccan secessionists, who waged a guerilla campaign against the Indonesian government from 1950 to 1963. The South Moluccans refrained from targeting civilians. They publicized incidents in which Indonesian troops bombed South Moluccan villages, erected starvation blockades, or used South Moluccan civilians as human shields. And they pleaded for help from the UN in the pages of The New York Times, but to no avail. Since losing the civil war, the South Moluccan secessionist movement has been represented by a government in exile in the Netherlands. Decades later, in the late 1980s, another group of Indonesian separatists, the East Timorese, adopted a policy of nonviolence after it became clear that they could not win their armed struggle against the Indonesian government. And both before and after they did so, the separatists worked to bring international attention to attacks by Indonesian security forces on peaceful protesters. (In 2002, after a UN-brokered transition, East Timor became an independent country.) More recently, in 2014, Kurdish forces in Iraq and Syria were extensively photographed assisting Yazidis who had been persecuted by ISIS. Yet it bought the Kurds little international support. The United States, for example, “strongly opposed” Iraqi Kurdistan’s 2017 independence referendum and threatened to end its dialogue with Iraqi Kurds should they proceed with their vote.

Kurdish fighters in Tel Abyad of Raqqa governorate, June 2015.
Kurdish fighters in Tel Abyad of Raqqa governorate, June 2015.

The preferences of major states and international organizations have influenced secessionists’ nonviolent actions, as well. Since the founding of the UN, the international community has generally frowned on unilateral declarations of independence. In the 1990s, during the Balkan wars that preceded the breakup of Yugoslavia, the British, French, and U.S. governments stated their opposition to such declarations. And in 1992, the UN Security Council issued a resolution on Bosnia and Herzegovina affirming that “any entities unilaterally declared . . . will not be accepted.” Secessionists have taken note: even though secessionism in civil war has increased since the turn of the twentieth century, the proportion of secessionists issuing formal declarations of independence has declined since 1945. 

Secessionists have usually gained little by defying this norm. During the breakup of Yugoslavia, Croatia and Slovenia issued unilateral declarations of independence. But the 1991 peace agreements that the European Community brokered to conclude their wars of independence required both countries to rescind those declarations. Both obliged, and within a year, both had become members of the UN. 

South Sudan’s declaration of independence, in 2011, provides an example of how to get secessionist diplomacy right. The South Sudanese worked with a New York–based nongovernmental organization (NGO), Independent Diplomat, to navigate a path to international recognition. Together, they met with representatives from international organizations, including the UN, to establish a set of guidelines for independence. As a result, when South Sudan declared independence, it did not do so unilaterally. It adhered closely to the provisions laid out in the 2005 Comprehensive Peace Agreement between the Sudan People’s Liberation Movement and the government of Sudan, which it correctly viewed as its best path to independence. The declaration was issued after the country was recognized by Sudan; the next week, South Sudan was voted in as a member of the UN, after its government followed a careful script that included President Salva Kiir handing the country’s declaration of independence to UN Secretary-General Ban Ki-moon.

Although states have been resistant to unilateral declarations of independence, a recent ruling of the International Court of Justice challenged that long-standing position. In 2010, the court issued an advisory opinion on the legality of Kosovo’s declaration of independence. It found that declarations of independence in general, and Kosovo’s in particular, are not illegal under international law. Many international lawyers (and the Kosovars themselves) argue that the ICJ’s opinion did not set a binding precedent. But several other would-be states, including Nagorno-Karabakh (which declared independence from Azerbaijan in 1991), Palestine, the Republika Srpska (a semiautonomous region within Bosnia and Herzegovina), and Transnistria (a breakaway region of Moldova), have indicated that they do see a precedent in the opinion, thus creating an opening for future unilateral declarations of independence.

Last year, two secessionist groups tested these waters. Until recently, Iraqi Kurdistan stepped extremely carefully around the question of declaring independence. But in September, the Kurdish government held a referendum against the advice of foreign allies, including the United States, in which 93 percent of Kurds voted for independence (although many of those in opposition to independence boycotted the referendum). The regional response was swift: Iraq cut off air access to Erbil, the capital of Iraqi Kurdistan, and Iran and Turkey (both of which have fought separatist Kurdish groups) moved troops to the region’s borders.

Catalan separatists also recently abandoned their historical reluctance to issue a formal declaration of independence, which stemmed from a fear that doing so would be received poorly abroad. That reticence made it surprising when the Catalan leader Carles Puigdemont decided to declare independence after the Catalans voted to leave Spain in a referendum in October 2017. Less surprising was Puigdemont’s instantaneous reversal. In the same speech in which he declared independence, he also suspended the declaration in order to allow for negotiations with the Spanish government and foreign countries and organizations. Despite this about-face, European officials criticized the declaration, and the Spanish government, which deemed the referendum and the declaration illegal, sought to arrest Puigdemont (who is currently in exile in Germany) on the charge of rebellion. Despite the ICJ’s opinion, international aversion to unilateral declarations of independence seems to be as strong as ever. 


Unfortunately for independence movements that have followed the rules, playing nice has rarely worked. The political scientist Bridget Coggins has shown that when it comes to gaining international recognition, having a great-power patron matters more than being on one’s best behavior. Take Iraqi Kurdistan and Somaliland. Both areas are well governed, especially compared with many of their neighbors. Their governments collect taxes, provide health care, and even conduct international relations to the extent that they can. Their militaries have mostly avoided targeting civilians, unlike nearby groups such as ISIS and al Shabab. Yet both governments have received little international recognition, which prevents them from providing many of the services one would expect of a modern state. They cannot issue travel visas, for example, or offer their residents an internationally recognized postal identity that would allow them to send and receive foreign mail. 

Bad behavior seems more likely to win international recognition. During South Sudan’s war for independence, opposing factions within the Sudan People’s Liberation Army, the military wing of the southern independence movement, attacked civilians who belonged to ethnic groups they saw as aligned with the other side. The brutality of their tactics, which included murder, rape, and torture, rivaled that of Sudan’s repressive central government. The South Sudanese authorities have also failed when it comes to the basics of governance: they have never been able to feed South Sudan’s population or deliver health care without international assistance. Yet none of these failures prevented South Sudan’s international supporters, including the United States, from championing the country’s independence. 

South Sudan’s experience is important in part because secessionists are becoming better observers of international politics and someday may decide that playing nice is not worth their while. Secessionists are increasingly connecting with one another, often with the help of NGOs. The Unrepresented Nations and Peoples Organization provides a forum for groups, including many secessionists, that lack official representation in major international organizations. It holds meetings at which its members can share information and strategies. Geneva Call, a humanitarian organization based in Switzerland, regularly reaches out to armed nonstate groups to train them in international humanitarian law and connects such groups with one another in order to increase compliance with the laws of war. Although both NGOs encourage separatists to abide by democratic and humanitarian norms, the more frequent contact that these organizations facilitate also allows secessionists to discuss which strategies have worked and which have not. They may very well conclude that good behavior has not been rewarded and note that separatists who have behaved badly have avoided punishment.

Cheap travel has also helped create a global separatist community. For example, in 2014, during the run-up to the Scottish independence referendum, Catalans traveled to Glasgow to wave their flag in solidarity with the pro-independence parties. There is now even an official soccer league for stateless nations (many of which include secessionists), the Confederation of Independent Football Associations. (Abkhazia, a breakaway region of Georgia, won the 2016 CONIFA World Football Cup.)

People celebrate South Sudan's independence in Juba, July 2011.
Thomas Mukoya / REUTERS


There are no easy answers to the secessionists’ dilemma. That is in part because secessionists have a complicated relationship with the principle of sovereignty, which underlies modern international relations. In one sense, they buy into the idea, as they would like to join the club of states themselves. But in order to do so, secessionists must violate the sovereignty of the country from which they secede. Existing states frown at the practice and tend to support one another in rejecting it; there is no right to secession in international law.

Yet if established states and international organizations continue to deny international recognition to secessionist movements that appear viable as states, separatists might abandon restraint and opt for violence. At the same time, any steps to give would-be governments more recognition would necessarily weaken the foundations of state sovereignty. 

There are ways to strike a balance between these competing interests. Concerned states and international organizations could offer some secessionists rewards that would enhance their autonomy but fall short of membership in blue-chip organizations such the UN. These could include invitations to join less well-known organizations whose work is nonetheless crucial for day-to-day international politics. Membership in the International Telecommunication Union, for example, would give secessionist groups more control over local communications infrastructure. Joining the IMF would open up access to loans. Having an internationally recognized central bank would allow self-governing secessionists to develop their financial markets. And membership in the World Bank’s Multilateral Investment Guarantee Agency would offer protection to foreign investors. 

Secessionists are becoming better observers of international politics.

Rewards along these lines would not be unprecedented. Kosovo is a member of the IMF, the World Bank, and the International Olympic Committee. Taiwan lost its membership in the UN to mainland China in 1971 but remains a member of the World Trade Organization, the Asia-Pacific Economic Cooperation forum, and the Asian Development Bank. And the Order of Malta, a religious military organization that is the world’s only sovereign entity without territory, maintains delegations at the African Union and the International Committee of the Red Cross and has a permanent observer mission at the UN.

Another option would be to further decentralize the process of recognition. Several states already recognize Kosovo and Palestine. Erbil hosts a number of consulates and offices representing international organizations and NGOs—thus receiving a tacit form of recognition.

In each case, major powers will have to weigh the benefits of soft recognition against political concerns. No matter how well Kurdistan is governed, for example, independence will always be a long shot given the fractured distribution of the Kurdish population among four neighboring and often antagonistic countries. And the fact that China and Russia, both permanent members of the UN Security Council, face their own internal secessionist movements means that they are unlikely to yield on the fundamental principles of state sovereignty and territorial integrity. But offering some carrots could help local populations and also create a boon for regional allies. Ethiopia and the United Arab Emirates, for example, are investing over $400 million in a port and military base in Somaliland, despite pushback from the internationally recognized government of Somalia. If Somaliland were a member of the World Bank’s Multilateral Investment Guarantee Agency, it would be able to attract even more foreign funding, as investors would receive some external protection.

The strongest secessionist groups, such as the government of Somaliland, the Iraqi Kurds, and the Catalans, appear to be the most receptive to international pressure because they believe they are the likeliest candidates for international recognition. Catalan secessionists, for example, refrained from violence even in the face of Madrid’s crackdown after last year’s independence referendum. If, however, secessionists come to believe that good behavior will not be rewarded, at least some of these groups will resort to violence, perhaps including terrorism. 

Continuing to frustrate secessionist groups will not keep them from pursuing their ends. Members of a secessionist movement often face a hard choice: remain among family and friends in an area that is relatively well governed but targeted by government forces or move across the putative secessionist border and face possible discrimination and isolation. Many who feel they are part of a movement will decide to stay, even in the face of international disapproval. Isolating would-be governments and giving their citizens reasons to feel aggrieved with the international system is a recipe for misery everywhere. Finding better ways of dealing with secessionism is therefore as much an issue for major countries and international organizations as it is for secessionists themselves.

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