Youth who immigrate to the US navigate unique and increasingly complex challenges. These challenges include stressful or unsafe sociopolitical pre-migration contexts, protracted or unpredictable migration processes, and post-migration stressors while adapting to a new culture. In this chapter, we examine such effects of immigration and acculturation on children in different historical periods. The example of migration from Mexico to the US is used to illustrate how our historical perspectives change and shape developmental possibilities and experiences for children. Our recent historical perspective embraced the goal of assimilating children and families into the US host culture, with little adherence to the values and traditions of the culture of origin. Over time this perspective has shifted to the current view that the goal of acculturation should be a bicultural one. Implications of various migratory paths for children’s adjustment are discussed, as are the developmental implications of current policies related to migration.

In this chapter, we argue that the timing of societal events in an individual’s life plays a major role in shaping that life through interacting developmental processes at multiple levels. We focus on classic research by Elder showing how two such events in historical proximity dramatically altered the lives of California children who were born at opposite ends of the 1920s, 1920–21 and 1928–29, the Great Depression of the 1930s followed by World War II (1941–45) and the Korean War (1950–53). We employ insights from both Elder’s cohort historical life course approach and developmental science including recent work on developmental neuroscience to understand the life-long impact of exposure to events that occur at different times in life, and the mechanisms through which these exposures may influence development, as well as experiences that may provide turning points in development.