In the last decade, research on atmospheric rivers (ARs) has surged due to their potential to cause extreme flooding and alleviate drought stress in the Western United States. Concurrently, wildfires in Southern California have become increasingly costly and destructive. While the timing of the first fall AR is known to influence wildfire risk in Southern California, the impact of ARs on spring vegetation growth and subsequent fall wildfire risk remains poorly understood, especially at the fine scale of Southern California ecosystems.

To investigate this link, we analyzed forty years of AR-associated Integrated Vapor Transport (IVT) and winter precipitation data across ten Level IV Ecoregions in Southern California. We examined the correlations between these metrics and the Enhanced Vegetation Index (EVI) and the Evaporative Demand Drought Index (EDDI). Our analysis revealed that productivity during the growing season is linked to the previous winter's total AR-associated IVT, and even more strongly to winter precipitation totals. We found positive correlations between AR-associated IVT and precipitation with EVI in early peak fire season (defined as August through October), particularly in chaparral-dominated areas, while conifer forests and grassland ecosystems displayed weaker correlations. 

We also found that the 90-day EDDI in early peak fire season was influenced by winter precipitation in some ecoregions, and that EDDI also had significant correlations with early peak fire season EVI. 

Our findings suggest that wet winters may increase wildfire risk in fuel-limited ecosystems like grasslands due to higher biomass accumulation, whereas in chaparral-dominated areas, increased moisture may reduce wildfire risk via maintaining higher fuel moistures in the fire season. These results underscore the need for further research to clarify the importance of fuel abundance versus fuel dryness, especially in conifer forest and sage scrub ecoregions for accurate Southern California wildfire risk assessment.

This dissertation examines the history of the exhibition “Heroic Defense of Leningrad” (1943-45) and its successor Museum of the Defense of Leningrad (1946-1953) in the context of the development of the war museum culture in the Soviet Union during the Second World War and the politics of war commemoration after its end. The museums constituted an important part of the war propaganda machine and were employed by the Soviet state to mobilize its population and to create an historical narrative of the war. In addition to the role of the central ideology, regional factors were as important in the creation of the war-themed displays, which I demonstrate by examining the war-themed exhibitions and museums in Kyiv, Minsk, and Moscow.The Museum of the Defense of Leningrad represented distinctly local narratives of the siege, including starvation in the besieged city. The attack and closure of the museum represented yet another step in the unification of the central narratives of the war during Late Stalinism. The ideological tendency of late Stalinism was to downplay the official commemorations of the war, which resulted in the closure of the vast majority of war exhibitions and museums. Yet, the fate of each individual institution also depended on the local factors, including the client-patron relationships between Stalin and the regional leaders, and between the regional leaders and the museums. The Museum in Leningrad was purged along with its former patrons during the course of the Leningrad Affair. The closure of the museum and other attacks on the memory and commemoration of the siege traumatized its survivors, hindered historical scholarship, and contributed to the discourse of the city’s victimhood. In addition to the history of the institutions, this dissertation examines the biographical case studies of the museum’s organizers, who survived the siege, worked to commemorate it, and then faced the political terror of late Stalinism.

The past several years have seen a national increase in mass shootings by white supremacists, many of whom have cited their belief in the supposed “Great Replacement” as a motivating factor for their violence. The “Great Replacement” is a far-right, white supremacist conspiracy theory that argues that the white race is being replaced by people of color, immigrants, and Jewish people. While several scholars have attributed the theory’s origins to the rise of the internet age and subsequent online communities for white power activists, this paper argues that “Great Replacement” ideology continues a white supremacist tradition of conspiratorial thought that dates back over a century, originating with the similarly named theory of “race suicide.”

In the late nineteenth and early twentieth century, different trends in immigration and the simultaneous rise to prominence of pseudoscientific racism in the United States led many prominent nativists to claim that the white race was committing “race suicide,” killing off its own race by allowing immigrants into the country and by having interracial children. This theory was intertwined with the rise of the early eugenics movement, a large-scale effort to strengthen civilization by promoting white reproduction and attempting to impede reproduction among “undesirable” populations. I use the case studies of two leading U.S. political figures and eugenicists–President Theodore Roosevelt and conservationist Madison Grant¬¬ –to demonstrate how the “race suicide” theory functioned as a pronatalist argument that encouraged white, “fit” women to reproduce. From the passing of the first Chinese Exclusion Act in 1882 to the 1924 Immigration Act, this paper charts the four-decade influence of the race suicide theory, which I argue further speaks to a continued tradition of white supremacist groups relying on “narratives of victimhood” to justify racial and xenophobic violence.

The Chilean coup d’état in 1973 led by General Augusto Pinochet impacted thousands of lives, changing several life trajectories. Among them, families had to flee the country to save their lives under a scenario of uncertainty and nearly after, when exile became a tool of state violence to repress the political left. In this context, historiography has mostly focused on adults to understand exile’s repercussions. If families were also composed of children, what do they have to tell us about this historical process?

This paper analyzes Chilean childhood experiences of exile from 1973 to 1990, arguing that examining this process allows us to understand exile as a tactic of political repression that impacted a generation of children beyond adults as the obvious “targets”. Moreover, by using children’s first-hand sources like drawings and audiovisual materials, I seek to understand the impacts of exile, mostly in a European context, on how this historical phenomenon was ingrained in children’s worldviews.

Thus, through the gaze of these historical actors and witnesses, we access the sphere of everyday life in exile, including changes in family dynamics and gender roles, adaptational challenges to a new society, and subjective struggles with identity and uprooting amid a new culture. In this sense, I propose the concept of “Double relational dynamic” which explains children’s political and personal concerns about Chile and their relationship as exiles with their host society.

As much as violence, racism, and cultural challenges were conveyed in their sources, children also registered a wider gaze finding spaces where they could talk, express, and imagine a Chile that has been elusive in their lives.

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In the immediate aftermath of the Sand Creek Massacre and a series of military conflicts with Indigenous peoples in the West, the United States Congress organized a joint special committee led by Wisconsin Senator James R. Doolittle in March 1865. Consisting of three Senators and four members of the House, the Doolittle Committee set out to inquire about “the conditions of the Indian tribes and their treatment by the civil and military authorities of the United States” in the Western territories. This article focuses on the experiences and debates surrounding the Doolittle Committee from 1865 to 1867 and, more broadly, the post-Civil War shifts in federal-Indian relations. Using Congressional documents, territorial newspapers, and personal writings, this article analyzes the objectives and experiences of the Doolittle Committee, the impacts of their findings on subsequent congressional commissions such as the Peace Commission, and the contested visions of settling the West after the Civil War. I argue that informed by postbellum reform movements, Doolittle and his colleagues initiated a significant, albeit short-lived, shift in federal-tribal relations. They imagined a possible future of these relations that had the potential to be more just and peaceful and projected an alternative vision of a righteous American empire. In examining the Doolittle Committee, this article joins historians of U.S. empire in emphasizing the contentious nature of postbellum U.S. imperial expansion. The workings of the Committee also offer insights into the non-linear trajectory of federal-Indian relations in the second half of the nineteenth century and demonstrate that the shifts in late-nineteenth-century evangelical reforms were already underway in the mid-1860s.

In January of 1847, in the northern New Mexico town of Taos, a combined force of Pueblos and Nuevomexicanos assassinated the U.S. territorial governor and marched on Santa Fe to contest the U.S. occupation. The U.S. Army eventually put down most of the resistance, and U.S. officials controversially held treason trials to condemn some of the revolt’s leaders. This paper asks how U.S. soldiers and officials made sense of their occupation of New Mexico during the U.S.-Mexico War (1846-1848), particularly in the wake of the Taos “Revolt” of 1847. It argues that U.S. soldiers and officials ultimately understood the Taos Revolt as a “revolt.” In doing so, they attempted to affirm U.S. sovereignty in New Mexico and to conceive of conquest as a single moment in time rather than as a process—though this understanding was far from stable or uncontested, even within U.S. ranks. Performance, whether in the form of stage plays or treason trials, was critical for constructing U.S. understandings of the occupation both before and after the revolt. This paper therefore asserts that performance was integral to the everyday mechanisms of empire. First, this paper analyzes the conquest-themed plays U.S. soldiers performed in Santa Fe on the eve of the revolt to understand how they grappled with the meanings of occupation and conquest. Then it turns to the Taos Revolt and the subsequent treason trials, in which U.S. officials tried Mexican citizens for treason against the United States. It argues that the trials were intended to act as performances of conquest and to produce a colonial history, but ultimately they underscored the instability and incoherence of “conquest.”

After the 1857 rebellion against British rule in India, British imperialists altered their mode of engagement with the princely states of India—from overt aggression exercised under the policy of “indirect rule” to restrained paternalism preached through a policy of “non-interference”. This paper seeks to illustrate how and why the goals of British imperialism evolved in the latter half of the 19th century. I undertake a case study of the largest princely state of India—Hyderabad—to illustrate that the Raj’s principle imperial agenda after 1857 was to domesticate and assimilate princely states within the colonial body politic. This was realized by rearticulating the tenets of ‘proper education’ for princely minors and selectively appropriating indigenous ritual idioms. In Hyderabad, I center the figure of the ‘princely minor’ Mehboob Ali Khan, the sixth Nizam of Hyderabad, whose minority from 1869-1884 became an opportune time for the British to reform and discipline him to mold him into an amenable ally. Leaving the policy of territorial conquest behind, after 1857, I argue that British imperialism had begun to envision novel ideological sites of colonialism.

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