The 27 January attack on Azerbaijan's embassy in Iran greatly impacted deteriorating relations between the two countries. During the incident, the head of security at the embassy was shot dead, and two other officers were wounded.
In response, Baku did not hesitate to immediately suspended work at its embassy in Tehran and evacuated all the staff and their families. Azerbaijani President Ilham Aliyev called it a "terrorist" act, and his government blamed Iran for not responding to security concerns they had raised before the attack.
On the Iranian side, the foreign minister and all high-ranking officials continued insisting that the attack was related to family issues between the assaulter and his wife, an Azerbaijani citizen. The claim was rebuked by their counterparts in Baku.
Tensions between the two countries have been high since the end of the 2020 Nagorno-Karabakh war. After the war, Iran accused Azerbaijan of permitting Israel to use its territory for spying on Iran. In return, Baku accused Tehran of supporting terrorist groups in Azerbaijan.
Then, the attack on the embassy happened. This incident looked more suspicious because of the long history of Iran's political tensions with other countries, followed by attacks on their embassies in Tehran. The raid on the Azerbaijan embassy was the last ring in the chain of targeting diplomatic missions in Iran.
Attacks on embassies in Tehran began in February 1829 when the Russian embassy was looted. The assault happened just one year after the end of the second Russo-Persian War (1826-1828), during which Iran lost large swaths of territories consisting of today's Armenia, parts of Georgia and southern Azerbaijan.
The motivation for the attack was Moscow's insistence on returning to Russia the Armenian and Georgian women who were married to Iranians. The invasion began with a gathering of people outside the Russian embassy. It ended in a gun battle and the ransacking of the embassy, which led to the death of the Russian ambassador Alexander Griboyedov.
After the killing of the Russian ambassador, for 150 years, no embassy was targeted in Iran. This changed with the 1979 revolution, and since, the frequency and number of assaulting embassies in Tehran dramatically increased.
The Shah's dictatorial regime collapsed on 11 February 1979, and just three days later, the US embassy in Tehran came under attack by the leftist guerillas. Since 1970, the guerillas had been fighting against the Shah, supported by the US and secured a total power grab after the CIA 1959 coup in Iran.
The interim government, consisting of prestigious nationalists and moderate leftists, stepped in rapidly and urged the guerillas to leave the embassy in a few hours.
A month later, on 26 March 1979, a group of 50 young men with their faces covered with the Palestinian Keffiyeh stormed the Egyptian embassy in Tehran in protest of the 1979 peace deal between Egypt and Israel. Since then, Iran and Egypt have never restored political ties.
And then came the most well-known embassy attack in the 20th century. At 10 am, on 4 November 1979, a group of Islamist hardliners called themselves the Muslim Student Followers of the Imam's Line stormed the US and demanded Washington hand over the Shah, who had been in the US since he was ousted.
The attack received full support from Iran's first supreme leader Rouhollah Khomeini. It resulted in the collapse of the interim government, the 444-day Hostage Crisis, the cessation of political relations with the US and the Islamists' success in controlling more political entities in the country.
Since then, it has become a habit for hardliner Islamists to assault foreign diplomatic missions in Tehran.
On 1 August 1987, the embassies of Saudi Arabia and Kuwait came under attack in protest to the death of Shia demonstrators in confrontation with the Saudi police during the Haj pilgrimage. One Saudi diplomat was killed in the attack, the Kuwaiti embassy was set on fire, and Riyadh cut political ties with Tehran for over ten years.
During the years that the pragmatic conservative Akbar Hashemi Rafsanjani (1989-1997) and the reformist Mohammad Khatami (1997-2005) were Iran's presidents, the diplomatic missions in Tehran experienced a safe and calm period. However, this changed when the hardline Mahmoud Ahmadinejad won the presidential elections in 2005.
On 6 February 2006, a group of 400 Basij paramilitaries attacked the Danish embassy in Tehran with Molotov cocktails, protesting over the publication of cartoons of the Prophet Mohammad in the Danish newspaper Jyllands-Posten. The paramilitary also attacked the Austrian embassy but could not enter the building.
Pakistan was another Muslim country whose diplomatic mission came under attack, however not severely. The raid happened in February 2009 and was led by a group of clerics, who threw stones at the windows of the embassy building, demonstrating against the killing of an Iranian diplomate in Pakistan.
After the reelection of Ahmadinejad in the contested June 2009 elections, international pressures and sanctions increased in Iran. On 29 November 2011, the Basij stormed the British diplomatic compounds in northern and central Tehran.
Without any reaction from the police, the paramilitaries entered the compounds, brought down the British flag, ransacked offices, took photos while holding the Queen's images upside down, and had a collective prayer in the embassy's garden.
In response, the UK closed its embassy in Tehran and expelled all Iranian diplomats and their families.
And then again Saudi Arabian embassy was targeted on 3 January 2016. This time the motivation for the attack was the execution of the Shia cleric Sheikh Nimr al-Nimr in a Saudi prison.
Apart from the embassy attack that led to the hostage crisis, in all other episodes, Iran said that the assailants were ordinary protestors unrelated to the government.
However, in a statement to the House of Commons after raiding the British embassy, the then British Foreign Secretary William Hague referred to the house arrest of opposition leaders, the crackdown on dissidents and a large number of executions in Iran, stressing: "the idea that the Iranian authorities could not have protected our Embassy or that this assault could have taken place without some degree of regime consent is fanciful."