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The archaeological and ecological record in California reveal a long history of wildfires in the state of California. In a study looking at pre-1800 wildfires, almost 1.8 million hectares were estimated to burn annually in California. This is about the level that has burned as of early October 2020in California. Scientists estimate that the summer and autumn seasons were often filled with smokey skies of burning forests. This could be because forest cover was generally more widespread in the past, resulting in larger fires. Fires were also seen as mostly healthy for forests, as newer growth would sprout more easily after fires.<ref>Stephens, S.L., Martin, R.E., Clinton, N.E., 2007. Prehistoric fire area and emissions from California’s forests, woodlands, shrublands, and grasslands. <i>Forest Ecology and Management</i> 251, 205–216. https://doi.org/10.1016/j.foreco.2007.06.005</ref>

One of the first major recorded California wildfires occurred in 1889; this fire is sometimes called the Great Fire of 1889 or the Santiago Canyon Fire. The fire mainly occurred in what are today's Orange, Riverside, and San Diego counties. Until 2018, this may have been the largest single wildfire event in California's recorded history, with over 300,000 acres burned. It started in September 24 and continued to September 30th. The fire was preceded by a very dry season, with only 0.4 inches of rain during the rainy season and strong Santa Ana winds were recorded that year. Other fires occurred that year, including in San Diego, but were far smaller. The 1871 Peshtigo Fire (Figure 1), which occurred in Wisconsin, influenced policy regarding wildfires in the late 19th centurythat also affected how fires were suppressed in California. Fire suppression strategies already began to be evident in places such as Yosemite, General Grant, and Sequoia national parksby the 1880s. The Peshtigo Fire covered 1.2 million acres and became the most deadly wildfire in US history, with 1500-2500 people killed in relatively rural areas of northeast Wisconsin. This devastation over a relatively low populated area resulted in a major policy move by authorities. The 1889 Santiago Canyon Fire also led reinforced, in the mind of authorities, to apply more intense fire suppression strategies to avoid loss of life and property. This meant that as soon as fires started, policy was to put out the fires as quickly as possible, rather than let them burn partially or completely out. Overall, these fire suppression strategies may have contributed to some of the larger fires that occurred much later, including in the 21st century, as it meant that forest growth was not renewed as quickly as would have been likely. This led to many older trees or even dead trees occupying large forest areas in many Western states, including in California.<ref>For more on fires in the 19th century and their influence on policy, see: US Department of Agriculture. 2015. <i>Ecological Foundations for Fire Management in North American Forest and Shrubland Ecosystems</i>. CreateSpace Independent Publishing Platform. </ref>