After Shah Jalal was summoned by the Sultan [[Shamsuddin Firoz Shah]] to take part in the [[Conquest of Sylhet]] against Raja [[Gour Govinda]], Haydar and the other companions joined him.<ref name="purbangsho">{{cite wikisource |script-title=bn:শ্রীহট্টের ইতিবৃত্ত - পূর্বাংশ |title=Srihattar Itibritta: Purbangsho |wslink=পাতা:শ্রীহট্টের ইতিবৃত্ত - পূর্বাংশ.pdf/১ |wslanguage=bn |last=Choudhury |first=Achyut Charan |authorlink=Achyut Charan Choudhury |year=1910 |location=Calcutta |publisher=Mustafa Selim |page=}}</ref>{{page needed|date=May 2020}}
Following the death of Sylhet's [[vizier|wazir]] [[Sikandar Khan Ghazi]], Sylhet became leaderless. Shah Jalal himself then appointed Haydar Ghazi as the second wazir to rule over Sylhet. It is unknown how long Haydar's governorship was but historians estimate his term finished some time after the death of Shah Jalal which was in 1346. The next known Wazir of Sylhet was [[Muqabil Khan]] who ruled in 1440.
After his rule in Sylhet, Haydar moved to [[Sonargaon]] where he spent the rest of his life.<ref name=hanif>{{cite book|title=Biographical Encyclopaedia of Sufis: South Asia|last=Hanif|first=N|publisher=Sarup & Sons|year=2000|chapter=Jalal, Shaikh (d.1357 A.D.)|pages=165–167}}</ref> His [[Mazar (mausoleum)|mazar]] remains in Sonargaon (in [[Dhaka Division]]).<ref name="akram">{{cite book|title=Muslim Banglar Samajik Itihas|page=66|author=[[Mohammad Akram Khan|Khan, Mohammad Akram]]|year=1956}}</ref><ref name=ali>{{cite book |script-title=bn:হজরত শাহ জালাল ও সিলেটের ইতিহাস |trans-title=Hazrat Shah Jalal and the History of Sylhet |last=Ali |first=Syed Murtaza |author-link=Syed Murtaza Ali |year=1965 |location=Dhaka |publisher=University Press |language=bn}}</ref>
