Where does “बीरगंज” come from?

बीरगंज (Hindi) comes from Nepali बीरगञ्ज, from Nepali बीर — brave, courageous.

Ancestry of “बीरगंज”, step by step

Step	Language	Word	Meaning
1	Nepali	बीरगञ्ज	—
2	Nepali	बीर	brave, courageous