Faisal II was deposed by a military coup on 14 July, and the new Iraqi government officially dissolved the Federation 2 August 1958.

[1] The Hashemites' most prominent rival for leadership in the 1950s was Gamal Abdel Nasser, the president of Egypt, the most populous Arab country.

The House of Saud ruled Saudi Arabia with Wahhabi religious fervor, and was also on poor relations with the Hashemites.

King Abdullah was assassinated in 1951 and one of the succession options explored was merging Jordan into Iraq, giving a combined throne to Faisal II.

The pact sought to block the Soviet Union from southward expansion and to prevent it from getting access to the petroleum resources of the Middle East.

He portrayed it as the first step among many, openly advocating for other countries to join the UAR, a direct threat to both Hashemite regimes which bordered Syria.

To counter Nasser's pan-Arabism, al-Said approached the Hashemite government of Jordan to discuss the formation of a similar union to appease Arab nationalists within Iraq.

With the fall and resulting deaths of al-Said, King Faisal II, and the rest of the Iraqi royal family, both the Hashemite regime fell and with it the short-lived Arab Federation.

Not only were King Hussein's ruling cousins in Iraq executed, but so was the Jordanian Prime Minister Ibrahim Hashem who was visiting at the time.

The Iraqi coup plotters who had ordered the execution of the Hashemites were themselves later overthrown and killed in the 1960s, perhaps easing the path to reconciliation.

By 1990 Iraq was "Jordan's largest market, it was repaying trade credit debts in oil, and it held out the hope of lucrative reconstruction contracts after the Iran–Iraq War.