The article examines the final stage of the political confrontations that took place in the Seljuk state at the end of the 11th and the beginning of the 12th centuries, specifically the struggle between Muhammad Tapar and Sultan Berkyaruq during the years 1099-1104. Known as the Interregnum period, this stage is characterized by internal fragmentation within the Seljuk authority and the weakening of central administration. The study highlights the emergence of the regions of Arran and Azerbaijan as key centers of conflict, emphasizing the particular role of Ganja due to its direct subordination to Seljuk rule. The article also analyzes the influence of prominent statesmen - such as Mawdud Yaquti, Mu’ayyid al-Mulk, Jawharayn, Zubayda Khatun, and Majd al-Mulk - on the course of the struggle. It further discusses how the confrontation between the sultan and the crown prince weakened the state and indirectly affected the Seljuks’ position in the Near East, particularly during the period of the First Crusade. By presenting the phases, causes, internal court intrigues, and consequences of the wars in chronological order, the article offers a comprehensive political panorama of the period.