- Since time immemorial: Tribal people live, fish, and sustainably manage the fisheries resources in what is now named the Columbia River Basin.
- 1805–06: The Lewis and Clark expedition, with assistance from numerous Tribal people and nations, travels along the Snake and Columbia rivers. Journals of the expedition reflect the size and importance of Columbia River salmon runs to Tribal people.
- 1830–50s: Large numbers of white settlers begin occupying Tribal territories in the Columbia River Basin, often violently excluding native people from their traditional lands and resources.
- 1855: Several Tribes sign treaties with the United States ceding large areas of territory in the Columbia River Basin. These treaties reserve the Tribes’ rights to take salmon at “all usual and accustomed places,” including along the Columbia and Lower Snake rivers.
- 1905: The Supreme Court (U.S. v. Winans) reaffirms that treaties prevent the States, or their citizens, from blocking Tribal fishing access. Justice Mckenna’s opinion notes that the right to fish is “not much less necessary to the existence of the Indians than the atmosphere they breathed.”
- 1925: The Yakama Nation petitions President Coolidge to defend treaty rights against infringement by the State of Washington. Yakama leaders travel to Washington D.C. to advocate for treaty rights.
- 1942: The Supreme Court (Tulee v. Washington) overturns the conviction of Yakama fisherman Sampson Tulee, reaffirming treaty fishing rights and ruling that tribal members do not need state-issued fishing licenses.
- 1950: The Washington Department of Fisheries opposes building four dams on the Lower Snake River because they would “jeopardiz[e] more than one-half of the Columbia river salmon production in exchange for 148 miles of subsidized barge route.”
- 1956–75: U.S. Army Corps of Engineers constructs four dams on the Lower Snake River, drowning the “usual and accustomed fishing places” protected by Tribal treaties.
- 1960–70: Tribal fishing rights advocates across the Pacific Northwest participate in “fish-in” protests—openly violating State fishing rules to highlight the loss of treaty fishing rights. The protesters are influenced by the American Civil Rights movement and collaborate with the NAACP and the ACLU.
- 1969–79: Tribal fishing advocates win a series of federal court cases (commonly called the Belloni and Boldt decisions) establishing the Tribes’ right to half of the harvestable salmon in the Columbia.
- 1982: Tribal fishing rights activist David Sohappy and others are targeted by the National Marine Fisheries Service and sent to federal prison for catching and selling Columbia River salmon.
- 1986: Snake River coho salmon go extinct. The Nez Perce Tribe begins reintroduction in 1994.
- 1991: The Shoshone-Bannock Tribes successfully petition the federal government to list Snake River sockeye salmon under the Endangered Species Act (ESA). Spring- and fall-run Snake River Chinook salmon are ESA-listed in 1992. Snake River steelhead are ESA-listed in 2006.
- 1994–2023: Tribes, states, and fishing and conservation groups repeatedly sue the federal government under the ESA for failing to create valid plans to recover salmon. Judges strike down multiple federal plans as inadequate and order marginal improvements to the dams to protect fish.
- 2008: Multiple Tribes and States sign the Columbia Basin Fish Accords, an agreement that guarantees federal funding to enhance fisheries and habitat. The Nez Perce Tribe and Oregon do not sign the Accords and, instead, continue opposing the management of the Columbia and Snake river dams by the Bonneville Power Administration and the Army Corps.
- 2017: Federal scientists, relying on decades of population modeling, show that Snake River spring and summer Chinook are unlikely to recover unless the Lower Snake River Dams are removed.
- 2018: The “Culverts Case” establishes that blocking salmon’s ability to migrate can violate the Tribes’ treaty rights to harvest salmon. As a result, the State of Washington will fix hundreds of culverts that block salmon migration.
- 2021: Representative Mike Simpson (R-ID) outlines an ambitious proposal to un-dam the Lower Snake River and invest in river communities.
- 2021: Tribal governments and institutions, including the Affiliated Tribes of Northwest Indians and the National Congress of American Indians, ask for Lower Snake River dam removal as part of a comprehensive plan to restore tribal fishing, culture, and treaty rights in the Columbia River basin.
- 2022: The National Marine Fisheries Service and the American Fisheries Society agree that removing Lower Snake River dams is essential to rebuilding abundant salmon and steelhead runs in the Snake River.
- 2022: The Biden Administration promises a durable strategy to restore abundant salmon and acknowledges that Lower Snake River dam removal is essential to that goal.
- Late 2023: The Biden Administration, Tribes, States, and groups including Columbia Riverkeeper sign a comprehensive agreement to recover Columbia Basin salmon, honor tribal rights, and replace the services of the Lower Snake River dams.
- June 2024: Following Tribal consultation, the U.S. Department of Interior publishes an analysis of the historic, cumulative, and ongoing effects of the Federal dams on Columbia River Basin Tribes.
- January 2025: The U.S. The Bureau of Reclamation publish a draft study showing that irrigation would remain feasible following Lower Snake River dam removal, given appropriate investments in new water infrastructure.
