Since the 1980s’, the Kaifeng Institute of Archaeology and Cultural Relics has conducted numerous salvage excavations throughout the municipal area of Kaifeng (see Supplementary Information). We have gathered stratigraphic, radiocarbon, and archaeological evidence that strongly supports the historical descriptions of the AD 1642 Yellow River flood from five recently excavated locations: Xinzhengmen, Yongning Wangfu, Dichen Xiyuan, Xinjiekou, and Yulongwan (see Fig. 1c, Table 1, and Supplementary Table 2).

Table 1 Accelerator mass spectrometry radiocarbon dates from Xinzhengmen, Yongning Wangfu, Yulongwan, and Dichen Xiyuan. Dates for each site are presented from oldest to youngest. The * indicates the date is anomalous. Dates are calibrated with BetaCal 3.21 using the IntCal13 dataset. Full size table

Xinzhengmen (S1)

At Xinzhengmen, archaeologists have opened up a 2,100 m2 excavation area, uncovering many architectural features that date to the Song, Yuan, Ming, and Qing dynasties18 (Fig. 2a). Two sections, one in the north and one in the south, were excavated down to the Qing dynasty land surface, while the rest of the excavation exposes the Song dynasty land surface. The trench is approximately 8 m deep and contains the remains of the Song dynasty city wall and gate (Fig. 2b). The foundations of the Song dynasty city wall are 23 m wide and are composed of rammed earth. The northern and southern sections of the excavation are about 4 m deep and contain evidence of several Qing dynasty house compounds buried by a Yellow River flood in AD 1841. Most of the exposed stratigraphy dates to the Ming dynasty occupation of the city, which itself contains a flood deposit that incised through many Ming dynasty strata (Fig. 2c). According to the ceramics found within these strata, archaeologists date this incised flood deposit to the AD 1642 Yellow River flood event.

Figure 2 Xinzhengmen. (a) Plan view of of Xinzhenmen with panoramas taken from locations (b,c). (b) View to the east. (c) View to the west. Full size image

We collected three radiocarbon samples from the eastern profile to determine the age of these flood deposits (Fig. 2c, Supplementary Fig. 1, and Table 1). We constrained the chronology of the incised channel by collecting two samples, one from below and one from above the incised channel, to provide a terminus post quem and a terminus ante quem for the flood deposit (Fig. 3a). The sample (Beta 53781) located directly beneath the incised flood channel returned a date of 950 ± 30 BP, which calibrated to AD 1024-1155 (95.4%) (Supplementary Fig. 2a). The second sample, 1.5 m above the incised flood deposit (Beta 535783), returned a date of 220 ± 30 BP, which calibrated to AD 1735-1806 (46.2%), AD 1642-1854 (37.9%), and AD 1933-post 1950 (11.3%) (Supplementary Fig. 2b,3a). Subsequent calibration of the first pair of dates at Xinzhengmen constrained the age of the flood deposit, making it highly likely that this incised flood deposit is part of the AD 1642 Yellow River flood event. A third sample (Beta 500051) from Xinzhengmen was collected from a buried tree found within the AD 1841 flood deposit and returned at date of 130 ± 30 BP, which calibrates to AD 1798-1894 (42.4%), AD 1674-1778 (38.0%), AD 1905-1942 (14.9%) (Supplementary Fig. 3b).

Figure 3 Stratigraphy at Xinzhengmen. (a) Sedimentary sequence including the incised deposit of the AD 1642 Yellow River flood and the overlying AD 1841 Yellow River flood, the red circles are placed at the approximate depths of samples for radiocarbon dating, see Supplementary Information for more details (b), data for particle size, loss on ignition, and magnetic susceptibility every 5 cm. Full size image

The excavations at Xinzhengmen have revealed a near continuous record of sedimentation from the Song to the Qing dynasties (Fig. 3a,b). Based on the radiocarbon and ceramic evidence, the stratigraphy contains deposits from the historically recorded Yellow River floods of AD 1642 and AD 1841. According to the particle size data collected from the eastern profile, the sediments from the Song dynasty and the Qing dynasty occupation layers are sandy loams that have higher magnetic susceptibilities than both the AD 1642 and AD 1841 Yellow River flood deposits (Fig. 3b). The AD 1642 Yellow River flood deposit is composed of two parts, a reddish silt-filled channel and an underlying sandy layer, presumably the channel’s bedload. Both parts of the AD 1642 flood deposit cleanly incised through cultural deposits, including cobble roads, bricks, and pottery, which provides a relative sense for the power of this flood event (Supplementary Fig. 4a,b). Around 2 m above the AD 1642 incised flood deposit is a 3 m thick sandy loam deposit that corresponds to the AD 1841 Yellow River flood. This flood deposit cleanly overlies the early Qing dynasty archaeological deposits at Xinzhengmen. This flood deposit contain many laminated beds that likely represent episodic flooding that occurred over many months, corroborating descriptions of the AD 1841 flood found in historical documents19,20.

Yongning Wangfu (S2)

At Yongning Wangfu, archaeologists excavated around 4,000 m2 to reveal the layout of a palatal compound where they found over 1,000 sets of porcelain and copperware, as well as stone tablets inscribed with family lineages and reign dates (Fig. 4a, Supplementary FigS. 5–7). Here, archaeologists have also found 15 skeletonized individuals that perished before or during the AD 1642 flood (Fig. 4b–g). Most of the human remains are highly fragmentary and disarticulated. The individuals that were articulated or partially articulated were found in a variety of positions, including both prone and supine with flexed limbs. Two individuals were found within wooden coffins and are presumed to have deceased before the AD 1642 flood. Aside from the human remains found within coffins, all the other skeletonized individuals appear to have died violently in the flood, disarticulated by debris and then buried within the mud left behind from the flood waters. These individuals are overlain by debris found within the flood deposit, including a wooden beam that appears to have penetrated an individual’s cranium and a large clay vessel which intrudes into another individual’s abdomen (Fig. 4f,g). Several meters above the AD 1642 flood deposit, archaeologists found a stela inscribed with the date of the 34th year of the Kangxi emperors’ reign, or AD 1695, indicating that people reoccupied the city around 50 years after the AD 1642 flood (Fig. 4h, see Supplementary Fig. 8b).

Figure 4 Yongning Wangfu. (a) Plan view of excavations at Yongning Wangfu with locations of AD 1642 flood victims and chronological information marked. (b–g) Victims of the AD 1642 flood. (h) Stelae dating to AD 1695 found in reoccupation layer. (i) Wood column sampled for radiocarbon dating. Full size image

At Yongning Wangfu, we have obtained three radiocarbon dates, one of which comes from a wooden column and the other two dates are from skeletonized individuals disarticulated by flood debris (Supplementary Fig. 9a,b, Table 1). One individual (Beta 535791) returned a radiocarbon date of 390 ± 30 BP, calibrated to 1440–1524 (69.2%), 1571–1630 (25.7%), 1559–1562 (0.5%), roughly corresponding with the AD 1642 flood event and the other individual (Beta 535792) returned a radiocarbon age of 330 ± 30 BP, calibrated to 1477–1642 (95.4%) (Fig. 4g). The wood sample (Beta 500052) returned a date of 340 ± 30 BP, calibrated to AD 1470–1640 (95.4%) (Fig. 4i).

The stratigraphy at Yongning Wangfu reveals that the AD 1642 Yellow River flood deposit is approximately 3 m thick and is primarily composed of silt loam (Fig. 5a–c, Supplementary Fig. 10). This profile contains stratigraphic evidence of the destructive power of the AD 1642 Yellow River flood as well as cultural layers that date to the reoccupation of the city during the early Qing dynasty. Large silt and sand “rip-up” clasts show that the flood was extremely turbid and that the mudbrick buildings dissolved into the otherwise clayey matrix of the Yellow River flood deposit (Fig. 5c). According to our particle size data, the flood deposit becomes less sandy up column, probably a result of the general reduction of the flood’s energy (Fig. 5d). As the flood lost energy, it deposited a reddish silt loam, typical of Yellow River flood deposits found nearby14,21. The flood deposits are clearly seen in the profiles exposed during the excavations at Yongning Wangfu. The high magnetic susceptibility values found in the Qing dynasty layer corroborates the archaeological evidence for a rapid reoccupation of Kaifeng after its destruction in AD 1642.

Figure 5 Stratigraphy at Yongning Wangfu. (a) Plan view of Yongning Wangfu with locations of profiles marked. (b) Southern profile with brick debris covered by silty clay loam with redoximorphic features. (c) eastern profile with AD 1642 flood deposit and overlying Qing dynasty reoccupation. (d) Data for particle size, loss on ignition, and magnetic susceptibility every 5 cm. Full size image

Dichen Xiyuan (S3)

At Dichen Xiyuan, archaeologists opened up a 3,700 m2 rescue excavation. Here, archaeologists found a large concentration of Ming dynasty buildings with pottery, porcelain and the remains of a large kiln (Fig. 6a–c, Supplementary Fig. 11a–c). Judging from the layout of the buildings, the site may be the western part of the Zhou Wangfu. We collected a piece of bark from a buried tree in a courtyard of a building for radiocarbon dating and the sample (Beta 535785) returned a date of 280 ± 30 BP, which calibrates to AD 1512–1600 (54.3%), AD 1616–1666 (38.3%), AD 1784–1795 (2.1%), and AD 1498–1502 (0.6%) (Fig. 6d, Table 1).

Figure 6 Dichen Xiyuan. (a) Panorama of excavations at Dichen Xiyuan. (b) Intact stratigraphic section of the AD 1642 Yellow River flood. (c) Overturned ceramic vessel containing intact AD 1642 flood stratigraphy. (c) Buried tree sampled for radiocarbon dating. Full size image

Xinjiekou (S4)

At Xinjiekou, archaeologists conducted rescue excavations and uncovered over 400 m2 of the former location of the Dianyi Suo (Office of the Rites), which was destroyed in the AD 1642 flood22. The archaeologists found artifacts that date to the late Ming through the late Qing dynasties, including a Ming dynasty courtyard that had collapsed houses and walls (Fig. 7a–c). Many artifacts were excavated from the site, including lacquered wooden wares, porcelain, pottery and other daily utensils. Within the courtyard, archaeologists unearthed a wooden plaque inscribed with the date of the tenth year of Emperor Chongzhen’s reign (AD 1637), providing a reliable chronological anchor for the site (see Supplementary Information).

Figure 7 Xinjiekou. (a–c) Excavations at Xinjiekou where the wooden plaque was found (artifact number JZ9: 308). Full size image

Yulongwan (S5)

At Yulongwan, archaeologists opened up an area of 970 m2 as part of a rescue excavation (Fig. 8a). The archaeologists found three buildings that date to the late Ming dynasty which contained over 3,000 artifacts (Fig. 8b). Many of these artifacts are coins that were cast during the late Ming dynasty. Archaeologists also found 11 skeletonized individuals, four of which were badly disarticulated, likely a result of a violent death in the AD 1642 flood. Among these individuals, two were found prone on a wooden bedframe (Fig. 8c). We sampled two individuals found at the site for radiocarbon dating (Table 1). One individual (Beta 535789) returned an age of 340 ± 30 BP, which calibrates to AD 1470-1640 (95.4%), and another (Beta 535790) returned a radiocarbon age of 330 ± 330 BP, which calibrates to AD 1477-1642 (95.4%), supporting the chronology provided by the material evidence found at the site (Fig. 8c).