Arsiyah (other forms of the word include - Lariçiyeh, al-Larisiya) was the name used for a group of Muslim mercenaries in the service of the Khazar Khaganate.
Which, according to the "Book of the Huns" by Alexandre Vincent, is translated from the Khazar language - guards.
[2] According to Muslim sources, the lariçiyeh formed the core of the Khazar army and were extremely influential in Khazar politics, but these assertions may be designed to exaggerate the importance of the Muslim community in Khazaria.
Part of the treaty binding them to Khazar service guaranteed that they would not be used to fight other Muslims.
In 913, the lariçiyeh ambushed a Varangian fleet that had been granted passage to the Caspian Sea by the Khazar government, wiping out thousands of Rus warriors.