While enamelled metal drinking-vessels date back to Antiquity, I am not sure how early the first pieces of enamelled glassware appeared. These pieces are almost always drinking-vessels -- though the shape and the decoration styles vary greatly. There are also several mosque lamps done in this style (these may be broken out into their own linkspage at some point in the near future).
The links are divided up by the region of origin (which work out to be roughly chronological clusters). Here are some more links on enamelling and glassworking . You can emulate this sort of decoration relatively easily if you'd like to paint your own feastware .
SYRIAN ENAMELLED GLASS, including Syro-Frankish ware
The Luck of Edenhall , a 13th century beaker
Footed bowl with an inscription, mid-13th century
Beaker with leather case ; the glass is from mid-13th century Syria, but the case was made in 14th-15th century Germany (also here , here , here , here , here , here , and here )
Beaker with saints and monasteries (?), c. 1260
Beaker with a figure riding a white donkey, c. 1260
Beaker, c. 1250-1270
Flask , c. 1260-1277
Bottle (also here ) with a phoenix, mounted warriors, and vegetal patterns, late 13th century
Vase with birds
Mosque lamp , mid-14th century (also here and here )
EGYPTIAN ENAMELLED GLASS
VENETIAN ENAMELLED GLASS
Glass beaker with harpies, attributed to Aldrevandini, second half of the 13th century
Glass beaker with armorial decorations, attibuted to the workshop of Aldrevandini, c. 1260-1290
A glass beaker with armorial decoration and an inscription, c. 1250-1320
Beaker , c. 1260-1270
Fragmentary beaker with Latin inscription (part of the "Ave Maria"), c. 1300
Fragments of beakers with saints, a pelican, and shields, c. 1300; see also this photo and caption
A so-called Syro-Frankish beaker with harpies, 14th century (also here , here , and here )
The Aldrevrandini Beaker , with an inscription and three heraldic shields, c. 1330
Glass goblet with armorial decoration, c. 1450-1500
Beaker , 15th or 16th century
Goblet with ladies and gentlemen and inscription, last quarter of the 15th century (also here , here , here , here , here , here , here , and here )
Goblet with profile portraits of a man and a woman, c. 1475-1500 (V&A 409-1854 )
Betrothal goblet with profile portraits of a man and a woman, with cherubs and a scroll and motto, the end of the 15th century
Two-colored goblet with gold and enamel decorations, c. 1475-1500
Goblet with abstract floral decoration, c. 1475-1510 (V&A 7536-1861 )
The Petronell Welcome , with abstract geometric decoration, c. 1480
Goblet with a pattern of interlaced tendrils, stylized palmettes, and daisies, late 15th century or early 16th century
Ewer , c. 1500
Beaker with "patera" decoration, early 16th century
Pilgrim flask with two boys standing in a landscape and holding a shield, c. 1500-1520
Glassware from 16th century Venice: goblet with enamel decoration on the edge (also here ) and a pilgrim's flask with the heraldry of a German family
FRENCH ENAMELLED GLASS
Betrothal goblet with a man and lady and inscribed scrolls (and a goat), made in mid-16th century France
Ewer with a man holding a banner, second half of the 16th century (also here and here )
CENTRAL EUROPEAN ENAMELLED GLASS
Armorial Designs (Wappenglas , Wappenhumpen , etc.)
Goblet with the arms of the Liechtenberg family, Bohemia, c. 1500-1530
Various 16th century German glasses
Goblet (Kelchglas ) made in Italy or Bohemia, mid-16th century
Tall beaker (Stangenglas ) with the heraldry of Joachim von Ortenburg and Ursula von Fugger-Kirchberg, 1554
Goblet with the heraldry of Michael Ludwig von Freiberg and his wife, made in Germany in 1566
Glass with inscription and heraldry of Ludwig Hausner, made in Nuremburg (?) in 1582
Beaker with the arms of the Schiltl family and the Portner von Theurern family, made in southern Germany in 1586
Glass with a crest, Germany, c. 1586-1600
Beaker (Stangenglas ) with the arms of Puchner, made in Bohemia or Germany in 1587
Glass (Stangenglas ) with the heraldry of Christoph Kneringer, made in Germany in 1589
Beaker (Stangenglas ) with the arms of Hirt and Maier (with mottos), made in southern Bohemia or eastern Bavaria in 1590
Glass (Wappenglas ) with heraldry, 1591
Stangenpokal made in southern Germany c. 1594-1600 (back , front detail , back detail )
Glass with heraldry, made in southern Germany or Saxony, 1595 (also here )
Beaker (Wappenhumpen ) with heraldry, made in Germany c. 1595 (also here )
Beaker (Wappenhumpen ) with heraldry, made in Germany c. 1595 (also here )
The Moritzburg Welcome , made in the Saxon-Bohemian Ore Mountains in 1602 (also here )
Goblet with heraldry, made in southern Germany in the early 17th century (also here )
Glass (Hofkellereiglas ) with the same heraldry on each side, 1610
Glass (Hofkellereiglas ) with different heraldry on each side, made in Saxony in 1611
Glass (Hofkellereiglas ) with heraldry, made in Saxony in 1612
Covered glass (Deckelhumpen ) with heraldry, from Moritzburg Castle, made in Saxony in 1612
Two footed bowls (Konfektschalen ) with heraldry, made in Nuremburg in 1614
Glass (Hofkellereiglas ) with heraldry and animals, made in Saxony in 1621 (also here , here , and here )
Glass with heraldry, from Moritzburg Castle, made in Saxony in 1621
Glass (Hofkellereiglas ) with heraldry, made in Saxony in 1621
Imperial Eagles (Reichsadlerhumpen , etc.)
The Prince-Electors (Kurfüstenhumpen , etc.)
Biblical Scenes
Covered tankard with Herod executing children, made in northern Bohemia (?) in 1578
Beaker (Stangenglas ) with the Annunciation, made in Bohemia in 1592
Cobalt-blue beaker with Elijah in the desert, made in northern Bohemia or Saxony in 1599
Glass with the Adoration of the Magi, made in Bohemia in 1604
Hunt Scenes (Jagdhumpen )
Other Scenes with People
Glass with ladies and gentlemen and an inscription, made in Bohemia in 1586
Glass with couples and musicians, c. 1590 (also here , here , here , and )
Glass with a couple amongst oversized foliage, made in Germany (?) in 1590
Covered glass (Stangenglas ) with a man riding a horse, 1597 (also here , here , and here )
Cylindrical glass with a scene of student life, Bohemia? c. 1600
Glass with ladies and gentlemen, 1604 (also here and here )
Glass with a lady and gentleman, Franconia, 1610 (also here and here )
Goblet with ladies and gentlemen and an inscription, made in Bohemia in 1613 (also here , here , here , and here )
Beaker of the Guild of Smiths & Locksmiths, made in Bohemia or Central Germany in 1614
Tankard with landscape and seated figures and heraldry, made in Silesia in 1616 (also here )
Other Designs
OTHER/UNKNOWN COUNTRIES OF ORIGIN
The Fairfax Cup, late 15th century (V&A C.17 to D-1959 )