Post-independence
The Treaty of London, signed by the British government and the Emir of Transjordan on 22 March 1946, recognised the independence of the state. On 25 May 1946, the day that the treaty was ratified by the Transjordan parliament, Transjordan was raised to the status of a kingdom under the name of the Hashemite Kingdom of Jordan in Arabic, with Abdullah as its first king; although it continued to be referred to as the Hashemite Kingdom of Transjordan in English until 1949. 25 May is now celebrated as the nation's Independence Day, a public holiday. Jordan became a member of the United Nations on 14 December 1955.
On 15 May 1948, as part of the 1948 Palestine war, Jordan intervened along with several other Arab states. Following the war, Jordan controlled the West Bank, and on 24 April 1950 Jordan formally annexed these territories after the Jericho Conference. In response, some Arab countries demanded Jordan's expulsion from the Arab League. On 12 June 1950, the Arab League declared that the annexation was a temporary, practical measure and that Jordan was holding the territory as a "trustee" pending a future settlement.
King Abdullah was assassinated at the Al-Aqsa Mosque in 1951 by a Palestinian militant, amid rumors he intended to sign a peace treaty with Israel. Abdullah was succeeded by his son Talal, who established the country's modern constitution in 1952. Illness caused Talal to abdicate to his eldest son Hussein, who ascended to the throne in 1953 at age 17. Jordan witnessed great political uncertainty in the following period. The 1950s was a period of political upheaval, as Nasserism and Pan-Arabism swept the Arab World. On 1 March 1956, King Hussein Arabised the command of the Army by dismissing a number of senior British officers, an act made to remove remaining foreign influence in the country. In 1958, Jordan and neighbouring Hashemite Iraq formed the Arab Federation as a response to the formation of the rival United Arab Republic between Nasser's Egypt and Syria. The union lasted only six months, being dissolved after Iraqi King Faisal II (Hussein's cousin) was deposed by a bloody military coup on 14 July 1958.
Jordan signed a military pact with Egypt just before Israel launched a preemptive strike on Egypt to begin the Six-Day War in June 1967, where Jordan and Syria joined the war. The Arab states were defeated, and Jordan lost control of the West Bank to Israel. The War of Attrition with Israel followed, which included the 1968 Battle of Karameh where the combined forces of the Jordanian Armed Forces and the Palestine Liberation Organisation (PLO) repelled an Israeli attack on the Karameh camp on the Jordanian border with the West Bank. Despite the fact that the Palestinians had limited involvement against the Israeli forces, the events at Karameh gained wide recognition and acclaim in the Arab world. As a result, there was an upsurge of support for Palestinian paramilitary elements (the fedayeen) within Jordan from other Arab countries. The fedayeen activities soon became a threat to Jordan's rule of law. In September 1970, the Jordanian army targeted the fedayeen and the resultant fighting led to the expulsion of Palestinian fighters from various PLO groups into Lebanon, in a conflict that became known as Black September.
In 1973, Egypt and Syria waged the Yom Kippur War on Israel, and fighting occurred along the 1967 Jordan River cease-fire line. Jordan sent a brigade to Syria to attack Israeli units on Syrian territory but did not engage Israeli forces from Jordanian territory. At the Rabat summit conference in 1974, in the aftermath of the Yom-Kippur War, Jordan and the rest of the Arab League agreed that the PLO was the "sole legitimate representative of the Palestinian people". Subsequently, Jordan renounced its claims to the West Bank in 1988.
At the 1991 Madrid Conference, Jordan agreed to negotiate a peace treaty sponsored by the US and the Soviet Union. The Israel–Jordan peace treaty was signed on 26 October 1994. In 1997, in retribution for a bombing, Israeli agents entered Jordan using Canadian passports and poisoned Khaled Mashal, a senior Hamas leader living in Jordan. Bowing to intense international pressure, Israel provided an antidote to the poison and released dozens of political prisoners, including Sheikh Ahmed Yassin, after King Hussein threatened to annul the peace treaty.
On 7 February 1999, Abdullah II ascended the throne upon the death of his father Hussein, who had ruled for nearly 50 years. Abdullah embarked on economic liberalisation when he assumed the throne, and his reforms led to an economic boom which continued until 2008. Abdullah II has been credited with increasing foreign investment, improving public-private partnerships and providing the foundation for Aqaba's free-trade zone and Jordan's flourishing information and communication technology sector. He also set up five other special economic zones. However, during the following years Jordan's economy experienced hardship as it dealt with the effects of the Great Recession and spillover from the Arab Spring.
Al-Qaeda under Abu Musab al-Zarqawi's leadership launched coordinated explosions in three hotel lobbies in Amman on 9 November 2005, resulting in 60 deaths and 115 injured. The bombings, which targeted civilians, caused widespread outrage among Jordanians. The attack is considered to be a rare event in the country, and Jordan's internal security was dramatically improved afterwards. No major terrorist attacks have occurred since then. Abdullah and Jordan are viewed with contempt by Islamic extremists for the country's peace treaty with Israel, its relationship with the West, and its mostly non-religious laws.
The Arab Spring were large-scale protests that erupted in the Arab world in 2011, demanding economic and political reforms. Many of these protests tore down regimes in some Arab nations, leading to instability that ended with violent civil wars. In response to domestic unrest, Abdullah replaced his prime minister and introduced reforms including reforming the constitution and laws governing public freedoms and elections. Proportional representation was re-introduced to the Jordanian parliament in the 2016 general election, a move which he said would eventually lead to establishing parliamentary governments. Jordan was left largely unscathed from the violence that swept the region despite an influx of 1.4 million Syrian refugees into the natural resources-lacking country and the emergence of the Islamic State of Iraq and the Levant (ISIL).