Updated April 8th, 2024:

• Changed the title from peacefully conquering 6 kingdoms to 12 kingdoms instead
• Corrected that the "Is a King" modifier ranges from -50 to -200 (rather than -100 to -200)
• Restructured the parts on Aquitaine and India into their own sections
• Included an updated screenshot of Aquitaine
• Added a section on the vassalization of the Armenian Principalities and Frisia
• Added a section on vassalizing England
• Added a section on vassalizing 3 kingdoms in Africa (Jenne, Ghana, and Mali)