Mousavian was born in 1957 to a prosperous carpet-dealing family in Kashan, a major carpet-manufacturing center. His family had close ties to the Motalefeh, a religiously oriented revolutionary movement that dated back to the early 1960s and was eventually absorbed into the Islamic Republican Party (IRP). Mousavian studied at the Iran University of Science and Technology, as well as Sacramento City College and Sacramento State University in the United States.
In 1981 he was awarded a Bachelor of Science degree in Engineering from Sacramento State University of California. He was awarded an MA in International Relations from the University of Tehran in 1998 and a PhD in the same subject from the University of Kent at Canterbury in 2002.
It has been speculated that Mousavian's father’s connections in Motalefeh helped him win access to leading IRP figures, as a consequence of which he was named editor-in-chief of the Tehran Times, the revolution's English-language newspaper, which was established by IRP founder Mohammad Hosseini Beheshti. During his editorial tenure, from 1980 to 1990, Mousavian authored more than 2,000 articles. He also held a number of positions in the Iranian government in the 1980s, including a stint as Vice President of the Islamic Propagation Organization (1981–1983), worked with future-President Hashemi Rafsanjani as Chairman of the Parliament Administration Organization (1983–1986), and was Head and then Director General of the West Europe department of the Foreign Ministry (1986–1989). During the 1980s, Mousavian played a major role in what he later described, in a 2012 book, as “Iran's humanitarian intervention to secure the release of Western hostages in Lebanon.” However, the hostage-takers (Hezbollah), had acted on instructions from the government in Tehran.
Mousavian was Iran’s Ambassador to Germany from 1990 to 1997. Four Iranian dissidents were murdered at Berlin's Mykonos restaurant in 1992, and five years later a German court concluded that Iran’s Special Affairs Committee had ordered the murders, and that the supreme leader, president, foreign minister and intelligence minister of Iran were all active members of that committee. The court found an Iranian intelligence officer and three Lebanese men guilty and issued an arrest warrant for Iran's intelligence minister. Also, Germany expelled four Iranian diplomats and asked that Mousavian be recalled to Iran; he did return to Tehran shortly thereafter. After the issuance of the arrest warrant for the intelligence minister, which Mousavian described as an insult to the entire population of Iran, Iranian news agencies made veiled threats against Germans abroad. Mousavian echoed, saying that if European nations kept treating Iran as America and Israel did, then they would be treated the same way by Iran.
It was also during Mousavian's ambassadorial tenure that the Salman Rushdie affair took place, and Mousavian went on German radio to announce that Iran would not lift its fatwa against the writer.
In the same interview, he expressed skepticism that Germany would risk its trade relations with Iran by protesting the Rushdie fatwa. Because of this statement, Social Democratic politician Freimut Duve called for Mousavian's expulsion, saying that he had, in effect, publicly expressed agreement with the fatwa; politicians from other parties echoed Duve's call. The German Foreign Ministry, moreover, summoned Mousavian to a meeting.
Subsequently, he headed the Foreign Relations Committee of the Supreme National Security Council (SNSC) of Iran during the eight years of Mohammad Khatami’s presidency. Mousavian meanwhile continued his education in the late 1990s, receiving a Master's degree from the University of Tehran in 1998 and a PhD from the University of Kent in the UK in international relations in 2002.
He later served as Foreign Policy Advisor to Ali Larijani, Secretary of the Supreme National Security Council (2005-7), and Vice President of the Center for Strategic Research and in a variety of capacities for the Expediency Discernment Council’s Center for Strategic Research (CSR) from 2005 to 2008. During this period he was Editor-in-Chief or a member of the Editorial Board for numerous CSR publications, including the Journal of Human Rights Studies, Journal of International Security and Terrorism, Rahbord (Strategy) Magazine, and Journal of Disarmament.
Mousavian played a role in a number of key developments during his more than two decades working on Iranian foreign affairs. He helped to secure the release of two German hostages held by Hezbollah in Lebanon from 1990 to 1993 and American and other Western hostages held in Lebanon in 1998–1999, as well as contributing to the mediation of the largest-ever humanitarian exchange between Israel and Lebanese Hezbollah under Germany’s auspices (1995–1996). Mousavian also played a role in Iran’s cooperation with the US in Afghanistan against Al Qaeda and the Taliban in 2001. From 2003 to 2005, Mousavian was Spokesman of the Iranian nuclear negotiation team, which in 2003 agreed for Iran to provisionally suspend uranium enrichment and allow inspections by the International Atomic Energy Agency at its nuclear sites as confidence building measures. In 2004, while head of the negotiating team, Mousavian asserted Iran’s sovereign right to pursue nuclear technology for civilian use and expressed satisfaction that the U.S. had been “isolated” at the IAEA in its attempt to pressure Iran. Mousavian’s team was replaced shortly before the election of Mahmoud Ahmadinejad as President in 2005, in tandem with Supreme Leader Ali Khamenei's announcement that Iran would resume enrichment activities.
Mousavian was arrested and briefly jailed by the Ahmadinejad administration in 2007 and publicly accused by the president of espionage for allegedly providing classified information to Europeans, including the British Embassy, before being cleared by the judiciary. There was speculation that his arrest was part of a factional struggle between Ahmadinejad and a triumvirate of his opponents: Akbar Hashemi Rafsanjani, Mohammad Khatami, and Hassan Rouhani, of whom Mousavian was considered an ally. After a year, a spokesman of Iran's judiciary announced that Mousavian had been cleared of the espionage charge after an investigation by three different judges. However, the third of those judges had sentenced him to a suspended term of two years in prison and to a five-year ban from holding official diplomatic posts because of his confessed opposition to the foreign and nuclear policy of President Ahmadinejad.
Accusations were renewed on August 22, 2010, when the Ministry of Intelligence issued a statement repeating the old claims publicly announced by Ahmadinejad in 2007. Mousavian’s lawyer has questioned this development, arguing that the Ministry of Intelligence statement ran contrary to the verdict reached three years earlier by the Iranian judiciary.
Mousavian has been a visiting research scholar at Princeton University’s Woodrow Wilson School of Public and International Affairs since 2009.
Writing in the Weekly Standard in September 2012, Reuel Marc Gerecht argued that Mousavian’s Western admirers, who see him as “a guide to a possible resolution” of the Iran crisis, “have been as naïve as he has been deceitful.... To journalists and American officials, he has tried with conviction to make the case for Tehran’s 'peaceful' nuclear program. For him, the Iranian regime is 'misunderstood,' and the West, even under President Obama, has been too hostile and suspicious. Sufficient Western concessions and greater Western sensitivity are the keys to solving the nuclear contretemps.” Mousavian's “assertions that Khamenei’s intent isn’t threatening,” noted Gerecht, “are followed by hints that a bomb might, nonetheless, be logical for the Islamic Republic to develop, especially given the threatening behavior of the United States and Israel.” Gerecht further pointed out that Mousavian, in his writings and talks, is consistently “respectful towards Supreme Leader Khamenei.”
Gerecht noted that "Mousavian at times claims to know a lot about Iran’s nuclear program, and then, when accusations from the IAEA are too cutting, not much at all." For example, "Mousavian knew not a thing" about the uranium-enrichment facility at Fordow until President Obama’s press conference about it. Citing Mousavian's expression of trust in "the supreme leader’s fatwa banning the use or production of nuclear weapons," Gerecht observes wryly that "Mousavian is putting his trust in the man who demolished his world, incarcerated him, and forced him and his family into exile. It would be easy to say that Mousavian is just lying—and he is. But what is more intriguing is how hard it is for him to reflect critically on the revolution. In his eyes still, Iran’s faults are mostly American in origin—or tactical mistakes made by his archenemy, Ahmadinejad. Like battered Communists of old who just couldn’t stop loving the Soviet Union, Mousavian remains a party apparatchik who still loves the cause....There isn’t a word, even from the safety of Princeton, about the dark side of Khamenei and his Revolutionary Guards’ having the bomb. Little men like Mousavian—ideologues whose identities were created by the revolution—just can’t flip."
Mousavian expressed deep concern about developments in Iran after that country's 2009 presidential election, but continued “to press for the U.S. to engage Tehran in a bid to reduce regional tensions,” according to a 2010 article by Jay Solomon in the Wall Street Journal. Mousavian believes that any future Iranian government will continue to pursue a nuclear fuel program, and that the U.S. should therefore improve relations with Tehran as a safeguard against an atomic weapons program. He also opposes UN sanctions against Iran, saying they “only serve to radicalize [Tehran’s] position.” Instead of imposing sanctions, the U.S. should “shape a comprehensive dialogue with Iran based on shared interests in stabilizing Iraq and Afghanistan” and “should develop with Tehran a broad security plan for the Persian Gulf that could prove crucial to securing the free flow of energy in and out of the strategic waterway.”
Mousavian dismissed as “politically motivated” the conclusions of a November 2011 report by the International Atomic Energy Agency (IAEA) that suggested “possible military dimensions” to Iran’s nuclear program.
Writing in National Interest in December 2012, Mousavian questioned the assumption by Western powers that “the best hope of altering Tehran’s nuclear policy and halting its enrichment activities” lies in “comprehensive international sanctions and a credible threat of military strike.” Mousavian maintained that "such punitive pressures... will not change the Iranian leadership’s mindset, and that a military option would be catastrophic" for everyone. Besides, he insisted, Iran has no interest in acquiring nuclear weapons. He offered ten reasons why this is the case, among them that developing nuclear weaponry would be considered “forbidden or haram” under Islam, would “trigger a regional nuclear arms race,” and would be contrary to Iran’s goal of becoming a modern nation.
In another December 2012 article, Mousavian argued that "U.S. strategists... should understand... the role of religion and clerics" in Iran. Noting that the world's “most powerful ideological-political party... is the Shia Cleric Organization in Iran,” he complained that “Western policymakers and some of their ‘Iranian experts’... have yet to realize that the clerical system... is a collective decision-making process, with heated discussions and debates among about twenty of the most revered Grand Ayatollahs in the country." Washington, he emphasized, “needs to recognize that Islam is the main source of Iranian power, and the religious establishments will play a key role in the future developments of Iran and the region....Instead of changing Iran’s government, the United States should focus its regional policy on three key areas: addressing the Palestinian issue, engaging moderate Islamists, and pursuing a regional security pact.”
In a January 2013 New York Times op-ed headlined "How to Talk to Iran," Mousavian and Mohammed Ali Shabani argued that there will be no “resolution of the nuclear standoff” between Iran and the West if Western leaders fail to grasp two key concepts: "maslahat," meaning "expediency, or self-interest" and "aberu," meaning "face – as in, saving face." For millennia, they wrote, "Persian culture has been distinguished by customs that revolve around honor and esteem....There are almost no instances in modern Iranian history when maslahat has trumped aberu. The West has poorly understood these concepts. This was particularly true under President Bush, who rewarded Iran’s tacit acceptance of the American invasion of Afghanistan by labeling Iran a member of an 'axis of evil.'" Mousavian and Shabani expressed the belief that "Iran would be open to new measures regarding the transparency of its nuclear program, and would agree not to pursue any capability to enrich uranium beyond that needed to fuel atomic power plants, if its legitimate right to enrichment under the Nuclear Nonproliferation Treaty was recognized and if an agreement to remove sanctions was reached."
Reviewing Mousavian's 2012 book, Iranian Nuclear Crisis: A Memoir in the Wall Street Journal, Sohrab Ahmari said that although the book “is billed as a memoir,” it is more of “a diplomatic brief, complete with awkward bureaucratic prose and key sections stippled by bullet points.” Ahmari drew attention to “the endnotes, where an editor apparently felt obliged to acknowledge where the author parts company with the public record,” as in an assertion that Iran had fully disclosed the details of its nuclear activities to the IAEA.