Editing Hexi Corridor (section)

=== Prehistory ===
The Hexi Corridor had been the site of east-west cultural exchanges across Eurasia since prehistory.{{Sfn|Dong|Yang|Liu|Li|2017}} It was first settled around 4800{{Nbsp}}[[Before Present|BP]] in [[Neolithic]] times by [[millet]] farmers from the [[Yangshao culture|Yangshao Culture]] in the western [[Loess Plateau]],{{Sfn|Dong|Liang|Zhang|2024|p=4: "Millet farmers settled in the northeast Tibetan Plateau and the Hexi Corridor during 5500–4300 BP, with broomcorn and foxtail millet being the primary crops in these two regions, respectively"}}{{Sfn|Dong|Yang|Liu|Li|2017|p=627: "The data indicate that millet farmers had settled in the Hexi Corridor by 4800 BP, with the production of painted pottery that originated from north China"}}{{Sfn|Li|Gao|Zhang|Duan|2023|pp=4-5: "[...] the Majiayao culture reaches an eastern section of the Hexi Corridor [...] In the Majiayao phase (4800–4450 BP), humans retain their traditional features and chose terraces with good water and heat conditions for their agricultural production in areas with thick loess accumulations."}} who enabled the spread of millet to [[Central Asia]] and the rest of [[Eurasia]] and [[Africa]].{{Sfn|Stevens|Murphy|Roberts|Lucas|2016|p=1544-1545}} These farmers also had [[pottery]] production techniques from Northern China.{{Sfn|Dong|Yang|Liu|Li|2017|p=627: "The data indicate that millet farmers had settled in the Hexi Corridor by 4800 BP, with the production of painted pottery that originated from north China"}} Several cultures developed in the Hexi corridor during this time, such as the [[Majiayao culture|Majiayao]], [[Banshan]], and [[Machang culture|Machang]].{{Sfn|Dong|Yang|Liu|Li|2017|p=622: "The Neolithic of the Hexi Corridor consists of three types of the Majiayao culture: the Majiayao (5000–4600 BP), Banshan (4600–4300 BP), and Machang (4300–4000 BP)"}}

The oldest [[bronze]] object to be discovered in China, dating to 5000–4500{{Nbsp}}BP, was found at the Majiayao site.{{Sfn|Chen|Cui|Liu|Wang|2020|p=954: "In this context, the Hexi Corridor is again at the heart of the discussion [...] It is within this region that archaeologists discovered the oldest bronze object so far in China (c.5000–4500 bp at the Majiayao site)"}} However, none of the Neolithic cultures in the Hexi Corridor at this time possessed the technology to smelt bronze, and only two sites had any bronze at all.{{Sfn|Dong|Yang|Liu|Li|2017|p=627: "The archaeological record during the Neolithic includes painted ceramics which appear in all sites of the Majiayao (4600–4000 BP) and Machang (4300– 4000 BP), but bronze vessels have only been found in two Machang cultural sites, Gaomuxudi and Zhaobitan in the central Hexi Corridor."}} As such, the [[Bronze Age]] only began in the Hexi Corridor around 4200{{Nbsp}}BP with the arrival of smelting technology from Central Asia,{{Sfn|Zhou|Li|Dodson|Zhao|2012|p=42: "After 4200 cal BP, the Qijia and Siba Cultures, which had copper smelting technology, prevailed in this region. Prosperous Bronze Age agriculture in the Hexi Corridor appears to have terminated suddenly around 3500-3400 cal BP"}}{{Sfn|Dong|Yang|Liu|Li|2017|p=625: "After the mid-fifth millennium BP, archaeological evidence from the Hexi Corridor suggests that cultural elements from east Asia spread to Central Asia by the way of the Hexi Corridor. For example, patterns of painted pottery spread to Xinjiang and then influenced Chust cultures in south Central Asia in the late Bronze Age. At the same time, the cultural elements of West Asia and the Eurasian steppes spread to east Central Asia and then to northwest China [...]"}} and the production of bronze reached its peak around 4000–3500{{Nbsp}}BP.{{Sfn|Zhang|Yang|Storozum|Li|2017|p=93-94: Fragmentary bronze artifacts were found in Majiayao (5000–4500 BP) and Machang (4300–4000 BP) late Neolithic cultures sites, but these findings are not reliable and need further validation. The number of bronze artifacts and sites with smelting relics reached a maximum during Xichengyi (4000–3700 BP), Qijia (4000–3500 BP) and Siba (3700–3400 BP) Bronze Age cultures period, but diminished substantially during Shanma (3000–2400 BP) and Shajing (2800–2400 BP) cultures.}} Domesticated [[livestock]] were also introduced to the area around this time;{{Sfn|Ren|Yang|Qiu|Brunson|2022|p=6: "The dispersal of domestic cattle and caprines along the Chinese Oasis route, including through the Hexi Corridor, probably occurred later than that of the more northern grassland route. Specifically, domestic cattle and sheep/goats may not have been introduced to the Hexi Corridor until ∼4000 BP"}} thus, these cultures typically farmed millet and wheat, while keeping livestock such as sheep, pigs, cattle and horses.{{Sfn|Yang|Shi|Zhang|Lee|2020|p=615: "During~2800–2000 BC, people in the Hexi Corridor adopted a sedentary lifestyle, cultivating millet and raising pigs, sheep/goats, cattle, and dogs. Moreover, they began to cultivate wheat and barley beginning ~2000 BC. By ~2000–1000 BC, the strategy had shifted to semi-sedentary agro-pastoral production, based on the utilization of sheep/goats,pigs, cattle, dogs, and horses. During ~1000–200 BC, wheat and naked barley replaced millet as the major crops"}}{{Sfn|Zhou|Li|Dodson|Zhao|2012|p=46-47: "The prosperity of Bronze Age agricultural societies in the Hexi Corridor persisted from ca. 4200 to 3500 cal BP, and was characterised by agro-pastoralist societies that kept livestock including pig, sheep, cattle and horse, while also producing bronze objects of alloyed copper, arsenic and tin"}} Bronze age societies in the Hexi Corridor at this time include the [[Shajing culture|Shajing]], [[Qijia culture|Qijia]], [[Xichengyi culture|Xichengyi]], [[Siba culture|Siba]], and [[Shanma culture|Shanma]] cultures.{{Sfn|Dong|Yang|Liu|Li|2017|p=622: "The Bronze Age cultures of this region include Qijia (4000–3600 BP), Xichengyi (4000–3700 BP), Siba (3700–3400 BP), Shajing (2800–2400 BP), and Shanma (3000–2400 BP)"}}

[[Wheat]] and [[barley]] from the [[Fertile Crescent]] arrived in the Hexi Corridor via Central Asia around 4000 BP,{{Sfn|Dong|Yang|Liu|Li|2017|p=623: "Charred seeds of wheat, barley, foxtail, and broomcorn millet are all identified from Huoshiliang and other Bronze sites in the central Hexi Corridor. This implies that wheat had been introduced to the Hexi Corridor region by at least the early fourth millennium BP"}}{{Sfn|Li|James|Chen|Zhang|2023|p=1: "Archaeobotanical and stable isotope evidence suggests that wheat and barley were introduced into the Hexi Corridor and northeastern Qinghai-Tibet Plateau in 4000 BP, rapidly replacing millets as primary staple crops after 3700 BP"}}{{Sfn|Stevens|Murphy|Roberts|Lucas|2016|p=1542-1544}} and later spread into [[China proper]].{{Sfn|Li|Dodson|Zhou|Zhang|2007}} By around 3700–3500{{Nbsp}}BP, most likely due to the continual weakening and retreat of the [[East Asian monsoon]] since 4000{{Nbsp}}BP which had caused increasing [[aridity]],{{Sfn|Zhou|Li|Dodson|Zhao|2012|p=42: "But the increasing climate aridity between ca. 4000 and 3500 cal BP, which was induced by a weakening of the Asian monsoon, is the underlying cause for the shrinking of arable land and vegetation degradation in Hexi Corridor, and this is the likely cause for the decrease of the agricultural activities and collapse of the Bronze Age societies in Hexi Corridor"}}{{Sfn|Li|Gao|Zhang|Duan|2023|p=4: "Since 4000 a BP, the East Asian monsoon decreases, and its range gradually retreats in the Hexi Corridor climate. In the eastern part of the Hexi Corridor, the cold and dry climate leads to the gradual retreat of ancient lakes and swamps, vegetation degradation, and the environment’s severe aridity... In the Siba culture (3650–3200 a BP), the climate becomes cold and dry, which causes the river systems to shrink and the land to become degraded [...] The sudden disappearance of the Siba culture could be attributed to two reasons. One is the weakening of the Asian monsoon and the extreme dry 3500 BP event, which causes a significant reduction in precipitation."}} the more drought-resistant wheat and barley had replaced millet as the main staple crop in the Hexi Corridor.{{Sfn|Li|James|Chen|Zhang|2023|p=1: "Archaeobotanical and stable isotope evidence suggests that wheat and barley were introduced into the Hexi Corridor and northeastern Qinghai-Tibet Plateau in 4000 BP, rapidly replacing millets as primary staple crops after 3700 BP"}}{{Sfn|Dong|Liang|Zhang|2024|p=7: "However, wheat and barley were adopted as important staple in the Hexi Corridor and the northeast Tibetan Plateau during 4000–3600 BP, respectively. This may be due to their adaptability to different altitude environments of these two regions, especially, barley is tolerant to low cumulative temperatures and precipitation, making it well-suited for successful growth in colder climates"}} Cultures after this time period (such as the Shajing culture) saw a decrease in site numbers and bronze artifacts,{{Sfn|Zhang|Yang|Storozum|Li|2017|p=93-94: Fragmentary bronze artifacts were found in Majiayao (5000–4500 BP) and Machang (4300–4000 BP) late Neolithic cultures sites, but these findings are not reliable and need further validation. The number of bronze artifacts and sites with smelting relics reached a maximum during Xichengyi (4000–3700 BP), Qijia (4000–3500 BP) and Siba (3700–3400 BP) Bronze Age cultures period, but diminished substantially during Shanma (3000–2400 BP) and Shajing (2800–2400 BP) cultures.}}{{Sfn|Zhou|Li|Dodson|Zhao|2012|p=42: "The subsequent Shajing cultures show evidence of cultural retrogression and site numbers are low until the rise of nomadic tribes after 3000 cal BP."}}{{Sfn|Yang|Shi|Zhang|Lee|2020|p=616: "The agricultural culture was entirely replaced by a pastoral culture, and the numbers of archaeological sites of the subsequent Shajing and Shanma Cultures are significantly smaller than that of the Siba Culture. During the subsequent millennium, Human settlement in the Hexi Corridor remained low, especially during 1350–950 BC [...]"}} and became dominated by nomadic production rather than agriculture.{{Sfn|Li|Gao|Zhang|Duan|2023|p=5: "The Shajing culture (2700–2100 BP) is the last prehistoric civilization in the eastern part of the Hexi Corridor. During that period, the [[Zhuye Lake]] has been shrinking due to drought caused by the further weakening of the East Asian monsoon [...] Shajing culture is dominated by nomadic production or mixed agriculture and animal husbandry production, and agriculture no longer dominates. With increasing drought levels, agricultural culture gradually declines and collapses, nomadic culture flourishes in the Hexi Corridor basin and animal husbandry prevailed."}}{{Sfn|Li|Zhang|Zhou|Gao|2023|p=|loc=Abstract: "In contrast, the Shajing Culture flourished along the lower Shiyang River with the retreat of the Zhuye Lake, the Xiongnu Empire established the city of Xiutu along the Hongshui River, which experienced downcutting linked to the arid environment, and a nomadic culture emerged against the backdrop of drought in the Shiyang River Basin"}}