The Achaemenid dynasty was one of the greatest empires in ancient eras, governing based on a monarchy around the king. Despite the presence of powerful rulers such as Cyrus and Darius, this dynasty was influenced by various factors that played a decisive role in different affairs, including politics. One of these factors was the aristocratic class, also known as the nobles and high-born individuals. The current study examines the role of this class in the political developments of the Achaemenid Empire and its impact until the end of Darius II’s reign. This research employs a library-based method and a descriptive-analytical approach based on primary sources and recent studies, aiming to answer this question and further identify this class in that era. The findings indicate that Persian nobles had a decisive role in politics. From the beginning of the Achaemenid dynasty, they played a determining role in various political and governmental affairs, such as the selection of kings and their successors, their overthrow, participation in councils, and even revolts against the central authority. By supporting members of the Achaemenid royal family, they had considerable influence during different rulers' reigns, so Darius I’s coup would not have been possible without the support and presence of the seven noblemen. Although some rulers, such as Cambyses, sought to reduce their influence and power, they encountered resistance and opposition from the nobles.