How did the Mughal Emperor Jahandar Shah’s reign come to an early end?

Jahandar Shah’s brief reign ended not by accidental death or deposition by his own wazir, but as a result of military defeat by his nephew Farrukhsiyar. Contemporary accounts state that Jahandar Shah was defeated at Agra in January 1713 by Farrukhsiyar, who owed his success to the powerful Sayyid brothers (Abdullah Khan and Husain Ali), and thereafter Farrukhsiyar was installed as emperor [1]. Sources further record that the Sayyid brothers played the decisive role in overthrowing Jahandar Shah and were rewarded with the highest offices (wazir and mir bakshi) after his removal and killing, confirming that his reign ended through battlefield defeat and subsequent elimination by rival claimants [2].

Sources

1. [1] Modern India ,Bipin Chandra, History class XII (NCERT 1982 ed.)[Old NCERT] > Chapter 1: The Decline of the Mughal Empire > The Decline of the Mughal Empire > p. 3
2. [2] Rajiv Ahir. A Brief History of Modern India (2019 ed.). SPECTRUM. > Chapter 4: India on the Eve of British Conquest > Weak Rulers after Aurangzeb—An Internal Challenge > p. 62