The northwest referred to in this book is limited to the four provinces and regions of Gansu, Ningxia (including the Alxa and Ejina Banners, now part of Inner Mongolia), Qinghai and Xinjiang during the Republican period, and the research objects include the Hui, Dongxiang, Sala, Baoan, Tibetan, Turkish, Mongolian and other ethnic groups mainly living in the Ganningqing region, and the Uygur, Kazakh, Kirgiz, Tajik, Uzbek, Tatar, Russian, Xibe and other ethnic groups mainly living in the Xinjiang region. Since the area is known as the Northwest Plateau, it actually consists of most of the Mengxin Plateau, the Qinghai-Tibet Plateau, and part of the Loess Plateau. According to the characteristics of natural ecological environment and ethnic distribution, the northwest region can be divided into two parts: Ganningqing region and Xinjiang region, so in the study of this book, it is often discussed from the two parts of Ganningqing region and Xinjiang region. Since ancient times, the Ganning Qingxin area has been a multi-ethnic area and a place where diverse cultures meet. During the Republican period, this multi-ethnic society experienced an important stage of development, played an important historical role, and began the transformation from a traditional society to a modern society under the impetus of the modernization trend in the eastern and central Han areas. Regarding the research on ethnic minorities in the northwest during the Republican period, the academic community has a certain accumulation. As early as the Republic of China, Chinese academic circles carried out academic research on the history and culture of Northwest Hui, Tibetan, Mongolian, Uygur and other ethnic groups. At that time, a large number of investigation reports, travelogues, travel notes, notes, anthologies and archives of the Republic of China all recorded or reflected the social conditions of the ethnic minorities in the northwest of the country to varying degrees, which provided basic information for us to systematically study the ethnic minorities in the northwest during the Republican period. In the 50s of the 20th century, the state organized many scholars to conduct an unprecedented social history survey of ethnic minorities, and then published the "Five Kinds of Books", including a brief history of ethnic minorities in Northwest China and a series of social history surveys, which collected a large amount of data on the modern and modern social history of ethnic minorities in Northwest China, laying a foundation for further promoting high-quality research on ethnic minorities in Northwest China. Since the reform and opening up, Chinese ethnohistoriography has developed rapidly and achieved fruitful research results. The four provinces and regions of Ganning, Qingxin organized and published a batch of literary and historical materials, which collected the memories of the parties concerned and supplemented and extended the previous historical records. In recent years, with the development of the western region, the study of the northwest frontier and nationalities in the Republic of China period has attracted more and more attention from the academic circles, and some scholars of history, ethnology, religious studies, and cultural anthropology have begun to actively participate in the study of ethnic minorities in the northwest during the Republican period, and research results have also emerged, which provide a good reference and reference for our further research. However, due to various reasons, the research on the history of the Republic of China started late, and the research on the history of ethnic minorities in northwest China during the Republican period is still a relatively weak link, and the existing research results have great limitations. The main manifestations are: First, in the research paradigm. Attaching importance to the history of political and revolutionary struggles and ignoring the changes in the social structure, economy and culture of various ethnic groups, many social fields and social problems cannot be contained by them, cannot generally show the social changes and internal laws of ethnic minorities in the northwest during the Republic of China, and also hinder the development and prosperity of ethnohistoriography. The second is at the level of research. Due to the relative lack of data on ethnic minorities in the northwest during the Republican period, and the scattered distribution, the previous academic research was mostly scattered and microscopic research, either the study of individual ethnic groups or the study of individual issues, lacking the overall grasp of macroscopic. Therefore, the selection of social changes in the northwest ethnic minorities during the Republic of China period for systematic research has both academic and practical significance. Academically speaking, first of all, based on detailed historical materials, this book conducts a more detailed study of the aspects of the significant changes in the society of ethnic minorities in Northwest China and their main problems during the Republican period, enriches the content of the research on the history of ethnic minorities in Northwest China, and expands the field of Chinese ethnic history research to a certain extent. Secondly, taking social change as the starting point, the basic historical process of the transformation of ethnic minority society in northwest China from tradition to modernity is described and analyzed in detail, which expands the horizon of ethnic history and Republic of China history research. Third, the characteristics and laws of social changes of ethnic minorities in northwest China during the Republic of China period are discussed in depth, which provides useful reference and reference for the study of ethnic minorities in northwest China in contemporary China. From a practical point of view, the study of practical problems can only be clearly seen in history. The Republican period was an important period in the historical evolution of ethnic minorities in Northwest China, and many ethnic issues existing today are directly and closely related to the historical development of various ethnic groups, and urgently need to be vigorously strengthened and studied. Therefore, the overall discussion and analysis of the social changes of ethnic minorities in northwest China during the Republic of China period is a topic of great social practical significance. It not only enables people to have a more comprehensive understanding of the historical original appearance of ethnic minority society in the northwest during the Republican period, understand the historical contributions of the people of all ethnic groups in the northwest to developing the northwest frontier, opposing foreign aggression and safeguarding the unity of the motherland, understand and sum up the historical experience and lessons of developing the northwest region during the Republican period, and enrich people's overall understanding of the minority society in the northwest during this period, but also through this research, a comparative and systematic summary of the imbalance, complexity and lag in the development process of ethnic minorities and ethnic minority areas in the northwest. A relatively systematic analysis of the factors that promote and restrict their social development in order to discover their unique laws provides a useful reference and reference for the study of minority issues in northwest China in contemporary times, provides multifaceted historical reference and certain theoretical support for the modernization of ethnic minorities in northwest China and the large-scale development of the western region, and is very beneficial to the correct implementation of the party's ethnic and religious policies, strengthening ethnic unity, and maintaining social stability of ethnic minorities in northwest China. Due to the lack and scattered research data on the population, economy and society of various ethnic groups in the northwest during the Republic of China, and the sources of statistical data are complex, some are actual census numbers or registered numbers, while others are completely estimates, and no separate statistics are made for the population of various ethnic groups, which has brought many difficulties to our research. We have collected and sorted out a large number of statistical data and literature on the population, economy and society of ethnic minorities in Northwest China during the Republic of China, and explained and explained them from the perspective of relevant issues and related disciplines, re-counted and analyzed some of the data, and corrected some deficiencies and errors caused by the limitations of the times. This book fully absorbs the research results of the academic community, takes social change as the starting point, and systematically discusses and analyzes the basic historical process of the transformation of ethnic minority society in northwest China from tradition to modernity during the Republican period. Social change is a sudden, sharp, evolutionary or slow change in social structure and social behavior, which is a dynamic manifestation of society. During the Republican period, due to unprecedentedly sharp ethnic and class contradictions, Chinese society underwent drastic changes in the face of the strong pressure of advanced Western civilization and the inherent requirements of Chinese society for modernization. Driven by the modernization trend in the eastern and central Han ethnic regions, the northwest ethnic regions began to transform from traditional society to modern society. Therefore, this book selects topics such as demographic change, modernity factors in traditional society, oasis agricultural change, educational change, social stratification and mobility, famine and social problems, Northwest warlords and Northwest ethnic society, etc., and generally highlights the aspects of significant social changes and their main problems. In addition, this book adopts a new perspective, and the narration and analysis of the intricate various characters in the northwest region during the Republican period are more in-depth, seeking truth from facts, holding appropriate arguments, and stepping out of the existing mind-set of the study of Republican characters. The research of this book reproduces from different aspects the complex process of tortuous development of ethnic minorities in northwest China under the influence of various epochal forces, in the interaction between tradition and modernity, new and old factors. Through research, we have a deeper understanding of the ethnic society in Northwest China during this period. First, the northwestern ethnic society during the Republican period had two distinct characteristics. First, the ethnic minorities in the northwest experienced an important development process during the Republican period, played an important historical role, and began the transformation from traditional society to modern society under the impetus of the modernization trend in the eastern and central Han areas, but the speed of transformation was relatively slow compared with the hinterland. The early modernization of the northwest belongs to the "late-onset exogenous modernization". Different from the "late-onset exogenous modernization" of China's mainstream society, the "late onset" of China's mainstream social modernization is relative to the time of modernization on a global scale at that time, while the "late onset" of modernization in Northwest China is relative to the more developed areas of China. The "exogenous" of China's mainstream social modernization refers to the Western capitalist world, while the "exogenous" of northwestern modernization refers to the early onset of China's internal modernization. The modernization of mainstream Chinese society began in 1840, while the northwest region began to change society after the reform of the state political system and the modernization trend of the Han region in the east. Both the elements of modern productivity and the elements of modern culture were transplanted or imported from outside. Therefore, compared with the Han areas in the hinterland during the same period, modern social factors are not fully developed, and traditional social factors are extensive, which makes the overall operation of ethnic society in the northwest not harmonious, social development lags behind, and all aspects of society are more complicated than in the hinterland. This difference determines that the early modernization in the northwest region has a low starting point, a late start, and a short time limit, and the transformation of the northwest ethnic society from traditional to modern society is more difficult and slow. Second, the ethnic society in the northwest during the Republican period showed diversified characteristics (including macro pluralism and micro pluralism), but there was a great imbalance in the transition of various ethnic societies from traditional society to modern society. Not only are there great differences between different ethnic groups, but the degree of social change is also inconsistent within the same ethnic group for various reasons. Due to the different ecological environments of various ethnic groups, the uniqueness of history and culture, the diversity of social composition, and the great differences in social consciousness, these factors affect their acceptance, digestion and understanding of modern social factors. The positive and progressive social factors of modern society are not consciously accepted by every nation, so when the transition of various ethnic societies from tradition to modernity, their overall social changes are not consistent. Second, the modernity factors that appeared in the northwest ethnic areas during the Republican period were still very weak, and it can be said that the traditional northwest ethnic society has gradually entered the threshold of modern civilization, but it is after all a sign of new progress, ushering in the dawn of modern civilization for this ancient and silent area, accelerating the process of social transformation of ethnic minorities in northwest China, and making historical preparations for the development and take-off of ethnic minority areas in northwest China after the mid-20th century. Third, although the minority society in the northwest during the Republican period began to move towards a modern society under the governance of the authorities, its development was still extremely slow and sometimes even retrogressive due to its remote location, backward transportation, fragile natural environment, strong traditional heritage, complex ethnic relations, different religious beliefs, frequent wars, frequent disasters and diseases, arbitrary rule by warlords, and the prevalence of nationalism and localism. Therefore, only after the founding of the People's Republic of China and under the leadership of the Communist Party of China and the implementation of the correct ethnic policy did the minority society in the northwest embark on the track of healthy and rapid development.（AI翻译）