Sivaslı, formerly known as Sebaste (Greek: Σεβαστή) is a town in Uşak Province in the inner Aegean region of Turkey.

[1] Sebaste ancient city area is 2 km (1.2 mi) away from Sivaslı town center today.

The ancient city of Sebaste was founded by Roman Emperor Augustus in 20 AD, and was one of the 12 important cities of Roman Phrygia.

[3] Under the Byzantine Empire, the city turned into a regional bishop seat.

There are remains of Byzantine buildings from the 6th and 10th century, including two large basilicas.