Short answers, pulled from the story.
The Qajar dynasty began in 1789 when Mohammad Khan Qajar unified Iran and ended on the 31st of October 1925 when Ahmad Shah fled Tehran. This period covered 136 years of continuous rule before Reza Shah established the Pahlavi dynasty.
Mohammad Khan Qajar founded the dynasty by unifying Iran through campaigns spanning from 1779 to 1796. The Qajars were originally a Turkoman tribe with strongholds in northern Iran that evolved from shepherd-warriors into a dominant political power under leaders like Shahverdi Qajar.
Naser al-Din Shah held the throne for the longest duration, reigning from the 5th of September 1848 until the 1st of May 1896 over 47 years. He adopted grandiose titles such as Shahanshah of Iran and Zell'ollah to reflect his perceived divine authority.
The Majlis convened on the 12th of December 1925 to declare Reza Shah the new monarch of Iran which ended the effective rule of the Qajar dynasty after 136 years. Ahmad Shah fled Tehran in 1925 as Reza Shah consolidated power before the Majlis formally dissolved the line in October 1925.
Abdol-Hossein Sardari worked as Consul General at the Iranian Embassy in Paris from 1940 to 1945. He helped save Jewish lives by issuing them with Iranian passports during the Holocaust era while serving as a descendant of the Qajar family.