The next year, he led an army that besieged Warangal, forcing the Kakatiya ruler Prataparudra to resume tribute payments to Delhi.
In 1320, he led a group of Baradus and disgruntled nobles to assassinate Mubarak Shah, and ascended the throne with the regnal name Nasiruddin.
In 1305, during the reign of Alauddin Khalji, they were captured when the Delhi forces led by Ayn al-Mulk Multani conquered Malwa in central India.
After consolidating his rule in Delhi, Mubarak Shah led a campaign to Devagiri in 1317, forcing the Yadava leader Harapala-deva and his prime minister Raghava to flee.
In 1318, Mubarak Shah sent an army led by Khusrau Khan, Malik Qutlugh, and Khwaja Haji to besieged Warangal, the capital of Prataparudra.
[12] Chronicler Ziauddin Barani writes that Khusrau Khan resented "the way the Sultan forced himself upon him and took advantage of him", and secretly planned revenge against him.
[13] Khusrau Khan also convinced Mubarak Shah to allow him to raise an army of Baradu Hindus by arguing that all other nobles (maliks) had their own groups of followers.
[16] Randhol, the maternal uncle of Khusrau Khan, entered the palace with a large number of Baradus, who hid daggers under their clothes.
When Ziyauddin let his guard down to accept a paan (betel leaf preparation) from Randhol, the Baradu leader Jaharya stabbed him to death.
According to the 16th century writer Firishta, even Malik Nusrat – who had renounced royal life to become a dervish – was killed, because he was the son of a sister of Alauddin.
[20] After killing the Sultan and potential claimants to the throne, the conspirators persuaded or compelled the various nobles to come to the first floor of the royal palace at midnight, and accept Khusrau Khan as the new king.
According to Barani, the following nobles were held as "hostages" at midnight: Ayn al-Mulk Multani, Wahiduddin Quraishi, Bahauddin Dabir, and three sons of Malik Qara Beg.
This marriage was declared invalid after Khusrau Khan was deposed, as according to the Muslim law, the widow could remarry only when four menstruation periods had passed after her husband's death.
[21] He claims that 5–6 days after Khusrau Khan's ascension to the throne, the Baradus and other Hindus started idol worship in the palace, and would sit on the Quran.
The Hindus rejoiced at Khusrau Khan's ascension, hoping to weaken the Muslims, and make Delhi a Hindu-majority city again.
[23] Additionally, Khusrau’s prohibition of cow slaughter alienated many Muslim nobles, who after just four months transferred their loyalty to Ghiyath al-Din Tughluq, a popular and experienced commander who had repulsed several Mongol invasions in the Punjab.
[24] Pakistani-Canadian academic Aziz Ahmad writes that after usurping the kingdom, Khusrau Khan "reverted to his ancient faith, began a reign of terror heaping dishonour on Muslim nobles".
Apart from Qazi Ziyauddin, whose wife and child had run away after his killing, the Baradus did not seize houses of Muslim nobles, many of whom were appointed to regular government posts under Khusrau.
Tughluq's son Fakhruddin Jauna, who held the office of akhur-bek in Khusrau Khan's government, was not happy with the regime at Delhi.
[29] As Tughluq raised a bigger army, and gained more support, Khusrau Khan's counselors advised him to take steps to prevent any further conspiracies and eliminate potential claimants to the throne.