According to the Corning Museum of Glass web site, glass making was discovered by potters in Mesopotamia, within the area now known as the countries of Iraq and Syria.“As early as 3,300 years ago, secret “instructions” for furnace building and glassmaking in Mesopotamia were written on clay tablets in a cuneiform alphabet. These instructions were copied and recopied over the centuries.” (From the Corning Museum site.) A glimpse of glass making in the 4th Century A.D. is provided by a huge glass slab found in Beth Shearim, Israel.
The Kelsey Museum in Michigan offers an introduction to their terrific site that takes you through their “Wondrous Glass” exhibition. It consists of ancient Roman glass dated from 50 BCE to 650 AD. There are a fantastic array of decorative techniques that were applied to glass wares such as you will see in these pictures of perfume flasks, jugs, decanters, and shipping jugs.
“Archaeological research now places the first evidence of true glass there [Mesopotamia] at around 2500 B.C. At first it was used for beads, seals, and architectural decoration. Some 1,000 years elapsed before glass vessels are known to have been produced. Vessels of glass quickly became widespread in the second half of the second millennium B.C. They were popular not only in Mesopotamia but also in Egypt and the Aegean.”
http://www.lsa.umich.edu/kelsey http://www.cmog.org/article/mystery-slab-beth-shearim