The Gravensteen at Ghent was the principal domain of the Hapsburgs in South Flanders. These stained-glass panels, thought to have come from this imperial residence, are part of a larger series ordered either by Maximilian I or Charles V. From left to right the arms are those of Maximilian I, Philip the Fair, Charles V, and Henry, count of Nassau.
Marking: Arms (of Philip the Fair): Quarterly, grand quarters I and IV, quartered,1 and 4, gules a castle or (Castile); 2 and 3, argent a lion rampant gules (León); II and III, quartered, 1, gules, a fess argent (Austria), 2, within a bordure compony gules and argent, azure, three fleur-de-lys, two and one, or (Burgundy Modern), 3 within a bordure gules, a bendy of six or and azure (Burgundy Ancient), 4, sable, a lion rampant or (Brabant), overall an inescutcheon, or a lion rampant sable (Flanders); encircled by the Colllar of the Order of the Golden Fleece.
Crest (on a barred helm): affronté or, a ducal crown surmounted by a lion sejant affronté crowned ducally of the last, grasping a target of the same and a sword proper; lambrequins or and ermine.
Probably from the Gravensteen at Ghent; Roy Grosvenor Thomas, New York and London (until 1937)
Steinberg, S. H. "A Flemish Armorial Window." The Burlington Magazine for Connoisseurs 74, no. 434 (May 1939). pp. 218–22, fig. A.
Caviness, Madeline H., ed. Stained Glass Before 1700 in American Collections: New England and New York (Corpus Vitrearum Checklist I). Studies in the History of Art, Vol. 15. Washington, D.C.: National Art Gallery, 1985. p. 137.