Although I take semantic issue with use of the term "aristocracy" when referring to the social organization of this still-poorly understood time period, the material culture found in the graves, and in surrounding and overlying archaeological stratigraphy, all make sense as belonging to the Red River plain Bronze Age sequence. The uppermost soil stratum was even reported to contain "a system of holes believed to be the outer most rampart of the Co Loa citadel," but this claim will certainly take more excavation over a wider area, and further analysis, to verify. Regardless of the final verdict, the recovery of an intact prehistoric site with burials in urban Hanoi is quite fortunate, as many of the objects, especially the ceramics and bronze artifacts, are common finds in urban "souvenir" shops, even if many of them turn up through field plowing in surrounding areas. Furthermore, uncontrolled development has damaged several sites throughout urban Vietnam. The fact that the Phung Nguyen burials were 1.5m under the modern ground surface no doubt helped preserve them. Hopefully, this is the first of a series of new sites that will be discovered and carefully excavated before they are destroyed as Hanoi continues to "modernize." Fingers crossed.
*=photo from Thanh Nhien Daily.com