An alleged plot to unseat King Abdullah II of Jordan unfolded in early April, unsettling a close U.S. ally in the Middle East.

Following what Jordan called a “threat to the country’s stability,” authorities said Saturday, April 3, that they had arrested nearly 20 people and limited the movement of former crown prince Hamzeh bin Hussein.

The Hashemite Kingdom of Jordan has been spared much of the political upheaval that’s rocked other capitals in the Middle East over the past decade.

But it has seen pro-democracy protest movements, been economically hurt by the coronavirus pandemic, and struggled to host more than 1 million refugees displaced by the war in neighboring Syria.

What you need to know about Jordan:

Who is Jordan’s King Abdullah II?

King Abdullah II, 59, has led Jordan since 1999. His family, the Hashemites, trace their lineage back to the prophet Muhammad.

Abdullah is the oldest son of the revered late King Hussein of Jordan and his second wife, Princess Muna. Abdullah is the half brother of Hamzeh, 41, who was detained as part of the alleged palace coup attempt.

Abdullah was educated abroad, including in England and the United States. He has also served in Jordan’s armed forces. He has four children with his wife Queen Rania, who is of Palestinian descent.

Abdullah has sought to cast Jordan as a moderate and stable regional force, and himself as a modern face of the country’s constitutional monarchy. Criticizing the king, however, is a crime in Jordan, while many other political rights and freedoms of expression are restricted. While Abdullah draws his legitimacy from the monarchy’s special status in Jordan, he has never attracted the same level of public support as his beloved late father.

In recent years, Abdullah has faced several waves of protests over economic issues, as well as calls for more political freedoms. So far, he’s successfully staved off these threats by reshuffling his government and making some political concessions. During Abdullah’s reign, it’s been rare for disagreements within the royal family to play out publicly.

What is Jordan’s modern history?

Jordan formally declared its independence from colonial British rule in 1946. Shortly afterward, Jordan joined in the fight against newly established Israel in the 1948 Arab-Israeli war. At the war’s conclusion, Jordan controlled East Jerusalem and the West Bank, and was home to many Palestinian refugees. Jordan then lost control of these territories to Israel in the 1967 war.

By some estimates, about half of Jordanians today are of Palestinian origin. The political system, however, has historically favored the country’s traditional tribes and rural populations, sometimes called East Bankers to distinguish them from originally West Bank Palestinians. (Some Palestinians in Jordan today have citizenship, while others do not.) Public sector jobs have also been dominated by Jordanians from tribal and rural backgrounds, while Palestinians have played a key role in developing the country’s private sector.

This tentative balance, however, has over the years been threatened by factors such as cuts to the public sector that have eroded the royal family’s traditional power base.

Why is Jordan a U.S. ally?

Jordan has cultivated close ties with a succession of U.S. presidents. It has also sought to maintain stable relations with its neighbors, including Israel. A peace treaty with Israel was signed in 1994.

During the Iraq War, Jordan was a key overland conduit to Iraq. It also hosted an influx of Iraqi refugees and served as a base for many international nongovernmental organizations. More recently, Jordan was a major partner in the U.S.-led campaign against the Islamic State and has assisted U.S. forces in security operations around the globe.

As a Sunni Muslim-majority country, Jordan has traditionally aligned with others in the region, such as Saudi Arabia and Egypt, and against Iran.

The Hashemite Kingdom is also keen to preserve its role as the custodian of holy Muslim and Christian sites in Jerusalem, including the al-Aqsa Mosque.

Who is Prince Hamzeh bin Hussein?

Hamzeh is the oldest son of the late King Hussein and Queen Noor, his American-born fourth wife. As of Saturday, he was reportedly at his Amman palace at the center of an investigation into the alleged plot to unseat his older half brother.

Hamzeh served for four years as crown prince before the designation was passed on to Abdullah’s oldest son, Hussein, in 2004. It was reportedly the late king’s intent that Hamzeh serve as crown prince.

Despite the downgrade, Hamzeh has remained a well-known figure in the royal family. He has held other positions within the monarchy and holds the rank of brigadier in Jordan’s army. Of the two brothers, he bears a more striking resemblance to former king Hussein. Hamzeh has reportedly cultivated ties with some tribal leaders disgruntled by parts of Abdullah’s rule.

In a statement delivered to the BBC by his lawyer on Saturday, the former crown prince denied the allegations and said he was being targeted for speaking out against corruption.

“I am not the person responsible for the breakdown in governance, for the corruption, and for the incompetence that has been prevalent in our governing structure for the last fifteen to twenty years, and has been getting worse by the year,” Hamzeh said in the statement.

His mother, Queen Noor, also tweeted in his defense. But by Monday, whatever quarrels remained had been quieted, at least for the time being, when Jordan’s royal court released a typed letter signed by Hamzeh declaring his allegiance to the king.

“The interests of the homeland must remain above all else, and we must all stand behind his majesty the king and his efforts to protect Jordan and its national interests,” said the letter.

The next day, Tuesday, Jordan issued a media gag order banning the publication of anything related to Hamzeh’s case. The restrictions came after an audio leaked of a conversation allegedly between Hamzeh and the head of Jordan’s army, who warned the former to stop criticizing the king on social media because the opposition was capitalizing on his posts.

How have other countries responded?

Other countries in the region, including Egypt and the gulf monarchies of Saudi Arabia and the United Arab Emirates, issued statements in support of Abdullah after Saturday’s news broke. The United States also reaffirmed its commitment to Jordan as a critical ally and source of security in the region.

Israeli Defense Minister Benny Gantz called the situation an “internal” issue in the only formal comment so far from Israel.

Jordan has officially refrained from calling the incident a coup attempt and has sought to quiet any concern over the country’s political stability.

Jordanian officials have said that “foreign” entities backed the effort. One Jordanian news site, Amon, which is tied to the Jordanian intelligence community, on Sunday accused Israeli businessman Roy Shaposhnik of being part of Israel’s Mossad and offering Hamzeh’s family his plane to escape Amman on. Shaposhnik, who is based in Europe, denied he was part of Israel’s intelligence agency but confirmed he had offered his plane to his friend, Hamzeh.

This report has been updated.