Reza Shah in the context of Tehran

Historically, Iran was commonly referred to as "Persia" in the Western world. Likewise, the modern-day ethnonym "Persian" was typically used as a demonym for all Iranian nationals, regardless of whether or not they were ethnic Persians. This terminology prevailed until 1935, when, during an international gathering for Nowruz, the Iranian king Reza Shah Pahlavi officially requested that foreign delegates begin using the endonym "Iran" in formal correspondence. Subsequently, "Iran" and "Iranian" were standardized as the terms referring to the country and its citizens, respectively. Later, in 1959, Pahlavi's son Mohammad Reza Pahlavi announced that it was appropriate to use both "Persia" and "Iran" in formal correspondence. A variety of scholars from the Middle Ages, such as the Khwarazmian polymath Al-Biruni, also used terms like "Xuniras" (Avestan: Xvaniraθa-, transl. "self-made, not resting on anything else") to refer to Iran: "which is the center of the world, [...] and it is the one wherein we are, and the kings called it the Iranian realm."

Mohammad Reza Pahlavi (Persian: محمدرضا پهلوی [mohæmˈmæd reˈzɒː pæhlæˈviː]) (26 October 1919 – 27 July 1980) was the Shah of Iran from 1941 to 1979. He succeeded his father Reza Shah and ruled the Imperial State of Iran until he was overthrown by the 1979 Islamic Revolution led by Ruhollah Khomeini, which abolished the Iranian monarchy to establish the Islamic Republic of Iran. In 1967, he took the title Shahanshah (lit. 'King of Kings'), and also held several others, including Aryamehr (lit. 'Light of the Aryans') and Bozorg Arteshtaran (lit. 'Grand Army Commander'). He was the second and last ruling monarch of the Pahlavi dynasty.

During World War II, the Anglo-Soviet invasion of Iran forced the abdication of Reza Shah and succession of Mohammad Reza Shah. During his reign, the British-owned oil industry was nationalized by the prime minister Mohammad Mosaddegh, who had support from Iran's national parliament to do so; however, Mosaddegh was overthrown in the 1953 Iranian coup d'état, which was carried out by the Iranian military under the aegis of the United Kingdom and the United States. Subsequently, the Iranian government centralized power under the Shah and brought foreign oil companies back into the country's industry through the Consortium Agreement of 1954.

The Pahlavi dynasty (Persian: خاندان پهلوی) was an Iranian royal dynasty that was the last to rule Iran before the country's monarchy was overthrown by the Iranian Revolution in 1979. It was founded in 1925 by Reza Shah Pahlavi, a non-aristocratic Iranian soldier of Mazanderani origin, who took on the name of the Pahlavi scripts of the Middle Persian language from the Sasanian Empire of pre-Islamic Iran. The dynasty largely espoused this form of Iranian nationalism rooted in the pre-Islamic era (notably based on the Achaemenid Empire) during its time in power, especially under its last king Mohammad Reza Pahlavi.

The dynasty replaced the Qajar dynasty in 1925 after the 1921 coup d'état, beginning on 14 January 1921 when 42-year-old soldier Reza Khan was promoted by British General Edmund Ironside to lead the British-run Persian Cossack Brigade. About a month later, under British direction, Reza Khan's 3,000–4,000 strong detachment of the Cossack Brigade reached Tehran. The rest of the country was taken by 1923, and by October 1925 the Majlis agreed to depose and formally exile Ahmad Shah Qajar. The Majlis declared Reza Pahlavi as the Shah of Iran on 12 December 1925, pursuant to the Persian Constitution of 1906. Initially, Pahlavi had planned to declare the country a republic, as his contemporary Mustafa Kemal Atatürk had done in Turkey, but he abandoned the idea in the face of British and clerical opposition.

The Sheikh Lotfollah Mosque (Persian: مسجد شیخ لطف الله, romanized: Masjed-e Shaykh Lotfollah;) is a Shi'ite mosque, located on the eastern side of Naqsh-e Jahan Square, Isfahan, Iran. Construction of the mosque started in 1011 AH (1602/1603 CE) and was finished in 1028 AH (1618/1619CE). It is one of the masterpieces of Iranian architecture from the Safavid era. It was designed by the chief architect Muhammad Reza during the reign of Shah Abbas the Great. On the advice of Arthur Upham Pope, Reza Shah Pahlavi had the mosque restored in the 1920s.

The Sheikh Lotfollah Mosque, completed in the Safavid style, is one of the most important architectural projects built on Isfahan's maidan, prominent for its location, scale, design, and ornamentation. The mosque is registered, along with the Naghsh-e Jahan Square and other surrounding structures, as a UNESCO World Heritage Site; and was added to the Iran National Heritage List on 6 January 1932, administered by the Cultural Heritage, Handicrafts and Tourism Organization of Iran.

Huwala (Arabic: الهولة, sing. Huwali هولي) also collectively referred to as Bani Huwala, are Iranian Arabs of tribal lineage who initially migrated to Iran in the 13th and 14th century and intermixed with the indigenous population of older Arabic-speaking background. Such migrations continued till around 19th century to the area which is now Iran's Hormozgan province and Fars province, mainly Bandar Abbas, Qishm, and the mainland near Bandar Lengeh. The Huwala follow Sunni Islam, like most Peninsular Arabs, and as opposed to the majority of Persians, who are Twelver Shia. Most of the Huwala have remigrated back to the Arabian Peninsula between late 19th century and early 20th century. The imposition of restrictive economic policies by Reza Shah in the 1930s led to the migration of most of the rest of the Huwala back to the Arabian Peninsula.

The term "Huwala" does not refer to Sunni Larestani Achomi families such as Awadhi, Kandari, Janahi, Khaloori, Zarooni, and Bastaki. It specifically refers to the actual Arab Huwalas (Arab El-Sahel), which encompasses the Qawasem, Hammadi, Al Nasur/Nassour, Obaidli, and Bani Tamim tribes.

The Imperial State of Iran, officially known as the Imperial State of Persia until 1935 and commonly referred to as Pahlavi Iran, was the Iranian state under the rule of the Pahlavi dynasty. The Pahlavi dynasty was created in 1925 and lasted until 1979 when it was ousted as part of the Iranian Revolution, which ended the Iranian monarchy and established the Islamic Republic of Iran.

The Pahlavis came to power in 1925 with the ascension to the throne of Reza Shah, a former brigadier-general of the Persian Cossack Brigade, and the overthrow of Ahmad Shah Qajar, the last Iranian ruler under the Qajar dynasty. Iran's Majlis, convening as a constituent assembly on 12 December 1925, deposed the young Ahmad Shah Qajar and declared Reza Shah as the new shah of the Imperial State of Persia. In 1935, Reza Shah asked foreign delegates to use the endonym Iran instead of the exonym Persia when addressing the country in formal correspondence. Reza Shah declared Iran neutral during the Second World War. Nonetheless, Iran was occupied by British and Soviet forces following the Anglo-Soviet invasion of Iran. Subsequently Reza Shah was forced to abdicate.

The Persian campaign or invasion of Iran (Persian: اشغال ایران در جنگ جهانی اول) was a series of military conflicts between the Ottoman Empire, British Empire and Russian Empire in various areas of what was then neutral Qajar Iran, beginning in December 1914 and ending with the Armistice of Mudros on 30 October 1918, as part of the Middle Eastern Theatre of World War I. The fighting also involved local Persian units, who fought against the Entente and Ottoman forces in Iran. The conflict proved to be a devastating experience for Persia. Over 2 million Persian civilians died in the conflict, mostly due to the Persian famine of 1917–1919, influenced by British and Russian actions. The Qajar government's inability to maintain the country's sovereignty during and immediately after the First World War led to a coup d'état in 1921 and Reza Shah's establishment of the Pahlavi dynasty.

The Anglo-Soviet invasion of Iran, also known as the Anglo-Soviet invasion of Persia or the Allied invasion of Iran, was the joint invasion of the neutral Imperial State of Iran by the United Kingdom and the Soviet Union in August 1941. The two powers announced that they would stay until six months after the end of the war with their mutual enemy, Nazi Germany (World War II), which turned out to be 2 March 1946. On that date the British began to withdraw, while the Soviet Union delayed until May, initially citing "threats to Soviet security", followed by the Iran crisis of 1946.

The invasion, code name Operation Countenance, was largely unopposed by the numerically and technologically outmatched Iranian forces. The multi-pronged coordinated invasion took place along Iran's borders with the Kingdom of Iraq, Azerbaijan SSR, and Turkmen SSR, with fighting beginning on 25 August and ending on 31 August when the Iranian government, under the rule of Reza Shah Pahlavi, formally agreed to surrender, having already agreed to a ceasefire on 30 August.

The Anglo-Persian Oil Company (APOC; Persian: شرکت نفت ایران و انگلیس) was a British company founded in 1909 following the discovery of a large oil field in Masjed Soleiman, Persia (Iran). The British government purchased 51% of the company in 1914, gaining a controlling number of shares, effectively nationalizing the company. It was the first company to extract petroleum from Iran. In 1935 APOC was renamed the Anglo-Iranian Oil Company (AIOC) when Reza Shah formally asked foreign countries to refer to Persia by its endonym Iran.

In 1954, it was renamed again to The British Petroleum Company, one of the antecedents of the modern BP public limited company. The government of Mohammad Mosaddegh nationalized the company's local infrastructure assets and gave the new company the name National Iranian Oil Company.

The Persian Cossack Brigade, also known as the Iranian Cossack Brigade (Persian: بریگاد قزاق, romanized: Berīgād-e qazzāq), was a Cossack-style cavalry unit formed in 1879 in Iran. It was modelled after the Caucasian Cossack regiments of the Imperial Russian Army. Until 1920, it was commanded by Russian officers, while its rank and file were composed of ethnic Caucasians and later on Iranians as well. During much of the brigade's history it was the most functional and effective military unit of the Qajar dynasty. Acting on occasion as kingmakers, this force played a pivotal role in modern Iranian history during the Persian Constitutional Revolution, the rise of Reza Shah, and the foundation of the Pahlavi dynasty.

1921 Persian coup d'état, known in Iran as 3 Esfand 1299 coup d'état (Persian: کودتای ۳ اسفند ۱۲۹۹ with the Solar Persian date), refers to several major events in Qajar Persia in 1921, which eventually led to the deposition of the Qajar dynasty and the establishment of the Pahlavi dynasty as the ruling house of Iran in 1925.

The events began with a coup by the Persian Cossack Brigade headed by Reza Khan on 22 February 1921. The precise level of British involvement in the coup remains a matter of historical debate, but it is almost certain that Edmund Ironside provided advice to the plotters. With this coup Ziaoddin Tabatabaee took over power and became prime minister. The coup was largely bloodless and faced little resistance. With his expanded forces and the Cossack Brigade, Reza Khan launched successful military actions to eliminate separatist and dissident movements in Tabriz, Mashhad and the Jangalis in Gilan. The campaign against Simko and the Kurds was less successful and lasted well into 1922, though eventually concluding with Iranian success.

Seyyed Zia al-Din Tabataba'i Yazdi (Persian: سید ضیاءالدین طباطبایی یزدی; June 1889 – 29 August 1969) was an Iranian journalist and pro-Constitution politician who, with the help of Reza Shah, spearheaded the 1921 Persian coup d'état and aimed to reform Qajar rule, which was in domestic turmoil and under foreign intervention. He subsequently became the 13th Prime Minister of Persia (Iran).

Bank Melli Iran (BMI; Persian: بانک ملی ایران, romanized: Bānk-e Melli-ye Irān, lit. 'National Bank of Iran') is a leading commercial bank in Iran, headquartered in Tehran. It was established in 1928 under the newly established rule of Reza Shah, and served as the country's central bank until 1960, when the Central Bank of Iran was established for that purpose and Bank Melli Iran was repurposed as a merely commercial bank.

As of 2016, Bank Melli Iran was the largest Iranian company in terms of annual income with a revenue of 364 657 billion rials in 2016. It was the largest bank in the Islamic world and in the Middle East. By the end of 2016, BMI had net assets of $76.6 billion and a network of 3.328 banking branches; so it was known as the largest Iranian bank based on the amount of assets. The brand of BMI was recognized as one of the 100 top Iranian brands in 10th National Iranian Heroes Championship in 2013. The National Bank has 3328 active branches inside, 14 active branches and 4 sub-stations abroad, and it has 180 booths.

A nationwide judicial system in Iran was first implemented and established by Abdolhossein Teymourtash under Reza Shah, with further changes during the second Pahlavi era.

After the 1979 overthrow of the Pahlavi dynasty by the Islamic Revolution, the system was greatly altered. The legal code is now based on Islamic law or sharia, although many aspects of civil law have been retained, and it is integrated into a civil law legal system. According to the constitution of the Islamic Republic, the judiciary in Iran "is an independent power" with a Ministry of Justice, head of the Supreme Court, and also a separate appointed Head of the Judiciary.

Mohammad Reza Pahlavi (26 October 1919 – 27 July 1980) was the Shah of Iran from 1941 to 1979. He succeeded his father Reza Shah and ruled the Imperial State of Iran until he was overthrown in the 1979 Iranian Revolution led by Ruhollah Khomeini, which abolished the Iranian monarchy to establish the Islamic Republic of Iran. In 1967, he took the title Shahanshah (lit. 'King of Kings'), and also held several others, including Aryamehr (lit. 'Light of the Aryans') and Bozorg Arteshtaran (lit. 'Grand Army Commander'). He was the second and last ruling monarch of the Pahlavi dynasty.

During World War II, the Anglo-Soviet invasion of Iran forced the abdication of Reza Shah and succession of Mohammad Reza Shah. During his reign, the British-owned oil industry was nationalized by the prime minister Mohammad Mosaddegh, who had support from Iran's national parliament to do so; however, Mosaddegh was overthrown in the 1953 Iranian coup d'état, which was carried out by the Iranian military under the aegis of the United Kingdom and the United States. Subsequently, the Iranian government centralized power under the Shah and brought foreign oil companies back into the country's industry through the Consortium Agreement of 1954.