The founder of the family was Kasım Ağaoğlu Alaaddin Bey. Therefore, the terms of Alaaddin Paşazade or Alaadin Quarry were also used to describe his descendants: Muş Beys, who are described as brave and brave warriors in the documents; their relations with the Ottoman government and provincial governors, their struggle with other gentlemen around them, their activities in the Ottoman-Russian and Ottoman-Iranian wars made them one of the most important families of the eastern provinces in the 18th and 19th centuries. Muş Beys did not only come to the fore with their warrior identities, but also contributed to the development of Muş with permanent works such as mosques, madrasahs, baths and bridges.