A Kebaya is a traditional blouse-dress combination worn by women in Indonesia. It sometimes made from sheer material and usually worn with a sarong or batik kain panjang, or other traditional woven garment such as ikat, songket with a colorful motif. The kebaya is the national costume of Indonesia, although it is more accurately endemic to Java, Sunda and Bali.
The earliest form of Kebaya originates in the court of the Javanese Majapahit Kingdom as a means to blend the existing female Kemben, torso wrap of the aristocratic women to be more modest and acceptable to the newly adopted Islam religion. Aceh, Riau and Johor Kingdoms and Northern Sumatra adopted the Javanese style kebaya as a means of social expression of status with the more alus pr refined Javanese overlords.
The name of Kebaya as a particular clothing type was noted by the Portuguese when they landed in Indonesia. Kebaya is associated with a type of blouse worn by Indonesian women in 15th or 16th century. Prior to 1600, kebaya on Java island were considered as a sacred clothing to be worn only by aristocrats (bangsawan) and minor nobility members of the Javanese monarchy, in an era when peasant men and many women walked publicly bare-chested.
Slowly it naturally spread to neighbouring areas through trade, diplomacy and social interactions to Malacca, Bali, Sumatra, Borneo, Sulawesi and the Sultanate of Sulu and Mindanao Javanese kebaya as known today were noted by Raffles in 1817, as being of silk, brocade and velvet, with the central opening of the blouse fastened by brooches, rather than button and button-holes over the torso wrap kemben, the kain (and unstitched wrap fabric several metres long erroneously termed ‘sarong in English (a sarung (Malaysian accent: sarong) is stitched to form a tube, like a Western dress) After hundreds of years of regional acculturation, the garments have become highly localised expressions of ethnic culture, artistry and tailoring traditions.
The earliest photographic evidence of the kebaya as known today date from 1857 of Javanese, Peranakan and Eurasian styles.
SOURCE : http://en.wikipedia.org