Short answers, pulled from the story.
The Pahlavi dynasty was founded in 1925 by Reza Shah Pahlavi, born Reza Khan, a non-aristocratic Iranian soldier of Mazanderani origin. The Majlis declared him Shah of Iran on the 12th of December 1925, acting under the Persian Constitution of 1906.
Reza Khan was promoted by British General Edmund Ironside on the 14th of January 1921 to lead the Persian Cossack Brigade. Under British direction, his force of three thousand to four thousand troops marched on Tehran, and by October 1925 the Majlis had deposed Ahmad Shah Qajar, ending the Qajar dynasty and paving the way for Pahlavi rule.
Pahlavi refers to the scripts of the Middle Persian language used during the Sasanian Empire in pre-Islamic Iran. Reza Khan chose the name to align the dynasty with pre-Islamic Persian identity, particularly the heritage of the Achaemenid Empire, rather than with the Qajar dynasty or Islamic traditions.
The Pahlavi dynasty's rule ended on the 11th of February 1979, when Mohammad Reza Shah was deposed in the Iranian Revolution. The dynasty had ruled Iran for fifty-three years since its formal establishment in December 1925.
Mohammad Reza Pahlavi was the last Shah of Iran, reigning from the 16th of September 1941 until he was deposed on the 11th of February 1979. He was the son of dynasty founder Reza Shah Pahlavi, and he adopted the title Shahanshah in 1967.
Reza Pahlavi, born in 1960, has been head of the House of Pahlavi since the 31st of October 1980, when his mother Farah Pahlavi's regency expired. His heir is Noor Pahlavi, his eldest daughter, who assumed that position on the 3rd of April 1992 following the death of his brother Ali Reza Pahlavi in January 2011.