Myanmar’s military staged a coup in 2021, strangling democratic reforms and jailing much of the country’s civilian leadership. Three years on, the Southeast Asian nation is teetering on the brink of failed statehood. Insurgent groups, including pro-democracy forces and ethnic militias, are battling the junta’s soldiers. Tens of thousands of people have been killed, and millions more are displaced.

The fighting, in forests and towns across Myanmar, gets little of the international attention claimed by the conflicts in Ukraine and Gaza. Yet a decade ago, this nation wedged between India and China was touted as a rare example of a country peacefully transitioning from military dictatorship toward democratic rule. The army putsch ended any illusion of political progress. Myanmar has returned to a military reign of terror and the fractured reality of civil war. The lawlessness that thrives in conflict areas has radiated outward, with transnational crime networks using Myanmar as a base and exporting the products of their illicit activity worldwide.

Why is there a civil war in Myanmar?

The short answer: The military coup was met by widespread peaceful protests. Then the junta, led by Senior Gen. Min Aung Hlaing, quickly reverted to its old playbook: jail, terrorize, kill.

Pro-democracy forces took up arms, joining with militias that for decades had been fighting for the rights of ethnic minorities.

The longer answer: Myanmar has been in turmoil practically since gaining independence from British rule in 1948. Some of the world’s longest-running armed conflicts have simmered in the country’s borderlands, where ethnic militias are seeking autonomy or simply freedom from the Myanmar military’s repression.

A brief period of political reform, with a civilian government led by Daw Aung San Suu Kyi, the Nobel laureate, did not make life much better for many ethnic minorities. After her political party trounced the military-linked party in Myanmar’s 2020 elections, a junta grabbed full control of the country again.

A common goal of overthrowing the junta has led to unity between pro-democracy militias and armed ethnic groups. Together, these resistance forces have claimed significant territory from the Myanmar military. On April 11, they captured a key border town from the junta’s forces, their biggest victory yet.

Who exactly is fighting the Myanmar military?

Hundreds of pro-democracy militias, ethnic armies and local defense forces. The sheer diversity of resistance groups battling the junta makes Myanmar the most fractured country on Earth, according to the Armed Conflict Location and Event Data Project, which tracks 50 high-level conflicts worldwide. Complicating matters, some of the rebel groups fight one another, too.

More than 20 militias representing various ethnic minorities have been fighting for autonomy for decades. Some of these insurgent groups control territory in Myanmar’s resource-rich periphery.

When ousted politicians and democracy advocates fled arrest after the coup, they found sanctuary in these ethnic rebel-held areas and formed a shadow authority called the National Unity Government.

Tens of thousands of young people — among them doctors, actors, lawyers, teachers, models, Buddhist monks, D.J.s and engineers — escaped from the junta-held cities and formed more than 200 People’s Defense Forces, pledging allegiance to the shadow government.

Often trained by the ethnic militias, the P.D.F. is now fighting in more than 100 townships across the country.

How successful have the rebels been?

Since an alliance of three ethnic armies, backed by the P.D.F., began an offensive on Oct. 27, the resistance has gained significant ground. Rebels now control much of Myanmar’s border region, including a strategic trading town that was captured on April 11. A few days later, they fired rockets at the nation’s top military academy. Some of the fighting is taking place within striking distance of Naypyidaw, the bunkered capital that the generals built early this century.

This year could be a turning point in Myanmar’s war, military analysts say. With each week, the junta’s forces abandon more outposts. Myanmar’s military is overstretched and underprovisioned. Even at the best of times, its biggest asset has been numbers, not expertise. In February, the military brought in a draft, signaling its desperation for fresh recruits.

How are civilians affected?

The Armed Conflict Location and Event Data Project says that the war in Myanmar is the most violent of the 50 conflicts it tracks. Since the coup, at least 50,000 people have been killed there, including at least 8,000 civilians, the group says.

More than 26,500 people have been detained for opposing the junta, according to the Assistance Association for Political Prisoners (Burma), a rights group.

Myanmar’s military has bombarded the country with airstrikes on over 900 days since the coup, according to the Myanmar Peace Monitor, an exile group that tracks the war. Since the rebels’ October offensive, there has been a fivefold increase in aerial bombardment, according to Tom Andrews, the United Nations Special Rapporteur for human rights in Myanmar.

By the end of last year, more than 2.6 million people had been driven from their homes in a country of about 55 million, according to the United Nations human rights office. Nearly 600,000 of those internally displaced people fled after the fighting intensified in October. More than 18 million people are in desperate need of humanitarian assistance, according to the United Nations, which says that a million had required such aid before the coup.

United Nations investigators say that the junta’s forces should be investigated for war crimes and crimes against humanity, and they cite reports of organized sexual violence, village burnings and the indiscriminate use of landmines. Such abuses predate the coup. In 2017, the military conducted what the United States says was a genocidal campaign against the Rohingya Muslim minority.

Who lives in the country?

Myanmar is an extraordinarily diverse nation whose borders were shaped by British imperialism rather than ethnic boundaries. Officially, 135 ethnic groups live in the country, and practically the only thing they agree on is that this figure is wrong.

Some ethnic minorities have more in common with people in China, India and Thailand than with the Bamar, Myanmar’s largest ethnicity. Others come from princely states that were not under the full authority of a central administration until the middle of the last century. Still others, such as over a million Rohingya, have been rendered stateless because the military refuses to recognize them as rightful inhabitants of the country.

What Myanmar’s ethnic minorities, particularly non-Buddhist ones, share is a long record of persecution by the military.

Myanmar’s ethnic diversity is concentrated in the foothills of the Himalayas and the forested border regions that cradle the delta and lowlands through which the Irrawaddy River flows.

Is it Myanmar or Burma?

It’s both.

In 1948, the Union of Burma declared independence from British rule. In the Burmese language, the root of the words Burma and Myanmar are the same. In 1989, a year after the violent crushing of a pro-democracy movement, a junta renamed the country internationally as Myanmar, the name by which it is known locally. The generals argued that Myanmar was a more inclusive name, because it was not so explicitly linked to the nation’s Bamar ethnic majority.

Nevertheless, the pro-democracy front, led by Ms. Aung San Suu Kyi, tended to refer to the country as Burma to show opposition to the military regime. Ethnic minority groups often called the country Burma when speaking English. The United States still officially calls the country Burma, but most foreign governments use Myanmar. After the 2021 coup, some exiled politicians and other pro-democracy activists who once called it Myanmar switched to Burma with an international audience.

Most people, however, still refer to Myanmar.

There is no commonly accepted word for the inhabitants of the country. Some refer to the Burmese of Myanmar, which seems a usage at cross-purposes. In Myanmar, the citizens are generally referred to as Myanmar, the word serving as both a nation and a nationality.

Will Myanmar hold together?

Three years after the coup, the center of Myanmar remains mostly under junta control, but the rest of the country is a kaleidoscopic array of competing influences, fiefs, democratic havens and drug-lord hideouts. Ethnic armed groups govern some areas. Administrators aligned with the National Unity Government have set up schools and clinics in others. No one is in charge in still other parts of the country, leaving residents lacking basic services and vulnerable to life in the margins.

The junta forces’ widespread use of landmines has made parts of Myanmar off limits. Within areas under the regime’s control, more than 100,000 civil servants refuse to turn up for work as part of a long-running civil disobedience campaign. Many of Myanmar’s most educated people are in exile or living in the jungles. Others are in prison.

The military is still the country’s largest and most influential institution, and a militarized culture pervades many areas that ethnic minorities control. The question is whether the Myanmar military will jettison Senior General Min Aung Hlaing, its supreme commander, if he is judged to be an impediment to the armed forces’ survival — Myanmar’s history is filled with military men being pushed aside for other military men. With more and more of its soldiers dying, the military is facing an existential threat.

It’s possible that a junta, perhaps not even the current one but a new coterie, will try to negotiate cease-fires with the many armed groups arrayed against it. But given the Myanmar military’s history of turning its guns against its own people, trust will be difficult to find.

The future of Myanmar will likely remain fractured, with no single authority in charge. Such a splintered state is likely to breed more chaos that will not be contained by national borders. Myanmar is again the world’s top opium producer, displacing Afghanistan. Some ethnic armed groups survive by churning out methamphetamine and other synthetic drugs. And the country is at the center of a cyber-scam industry that steals billions of dollars from unsuspecting people and kidnaps others to forcibly work the cons.