26th February 1411 is not the foundation day of Ahmedabad. Rather, it is conquest day.
On this day, the city of Karnavati established by Karnadeva was destroyed. Citizens were conquered and enslaved. The new city of Ahmedabad was built from the ruins of the erstwhile Karnavati.
Written more than a 100 years before Ahmad Shah, Prabandha Chintamani describes the formation of the city of Karnavati by Karnadeva.
It also describes that he built a temple to the Goddess named Kocharaba. This book was written before the birth of Ahmad Shah.
The earliest buildings of Ahmedabad like the Bhadra fort and Jami Mosque were built from Hindu temples which existed earlier in that place.
Source: “The Making of old city of Ahmedabad” by Matthijs van Oostrum
(This article has been compiled from the tweet thread originally tweeted by True Indology (@TrueIndology) on February 26, 2023.)