The Betawi people are an old ethnic group originating around Batavia in the 17th century. There is a Betawi Cultural Centre around the Setu Babakan lake near my family in Jakarta.
Here is an interesting discussion on the Betawi culture by Gunawan Tjahjono, which
"... examines the various conditions that gave rise to a new ethnic group, the Betawi, from the diverse origins of people who settled in the area of today’s Jakarta, Indonesia. It first traces the identity-formation process of the Betawi, then examines how Betawi culture has been challenged recently by the development of Jakarta as a global city. As Indonesia’s central government has del- egated more authority to localities since the end of the New Order era, the municipality of Jakarta has attempted to revive Betawi identity through development of a Cultural Village in Setu Babakan, a place where Betawis are actually a minority. However, it is questionable whether such architectural intervention either has had, or will have the desired effect on cultural revival."