About Expo & Its History

The Japanese American Museum of Oregon is to preserve and honor the history and culture of Japanese Americans in the Pacific Northwest, educate the public about the Japanese American experience during WWII, and advocate for the protection of civil rights for all Americans.

The Vanport Mosaic is a memory-activism platform. We amplify, honor, and preserve the silenced histories that surround us in order to understand our present, and create a future where we all belong. We co-created the most extensive collection of first-hand memories of life in Vanport, the devastating flood, and its aftermath.

The Oregon Historical Society is dedicated to making Oregon's long, rich history visible and accessible to all. Our research library, museum, digital platform, educational programming, and historical journal make Oregon's history open and accessible to all. We exist because history is powerful, and because a history as deep and rich as Oregon's cannot be contained within a single story or point of view.

The site was historically used by Indigenous populations, who relied on the nearby Columbia River for fishing and other resources. This marks the beginning of the land's recorded human history.

Originally constructed as livestock exhibition halls under the auspices of the Pacific International Livestock Association in 1921. Three years later, the complex of buildings burned to the ground but was rebuilt in 1925. To this day, Halls A and B continue as 84,000 square feet of rentable space.

Expo served the North Portland Stockyards and nearby meat processing plants through the 1950s as a livestock exposition center, cattle grading center, auction facility and venue for first‐class rodeos. In the 1930s it was the largest livestock exhibition center on the West Coast.

In 1942, the Portland Assembly Center, now the Expo Center, served as a temporary holding facility for over 3,500+ Japanese Americans forced from their homes during World War II. As part of Executive Order 9066, these individuals were detained here for several months before being sent to more permanent internment camps. This history remains a significant reminder of the injustices faced by Japanese Americans during the war.

The Portland Assembly Center was hastily converted from livestock exhibition halls into barracks-style living quarters. Detainees endured cramped conditions, poor sanitation, and a lack of privacy. Despite these hardships, the Japanese American community showed remarkable resilience, organizing schools, medical services, and religious gatherings within the camp.

The history of the Portland Assembly Center is now commemorated in partnership with local organizations like the Japanese American Museum of Oregon. These efforts ensure that the stories of those held here are remembered, fostering greater understanding of the lasting impacts of wartime internment on the Japanese American community.

The flood occurred on May 30, 1948, when a catastrophic failure of a dike on the Columbia River led to the flooding of the city of Vanport. Vanport was a hastily constructed wartime housing project, primarily accommodating workers who supported the war effort. The city was home to a diverse population, including a significant number of African Americans who had migrated for employment opportunities.

The flood resulted in the complete destruction of Vanport, displacing over 17,000 residents and leaving many homeless. Tragically, 15 people lost their lives in the disaster. The Vanport flood is a poignant chapter in Oregon's history, underscoring the vulnerability of hastily constructed communities and the importance of infrastructure planning. The event had a lasting impact on the affected individuals and highlighted the need for improved flood control measures in the region.

Following its WWII use, the site transformed in the 1950s into a civic space for public gatherings, hosting agricultural shows, trade fairs, and community events that bolstered Portland’s economy. Officially renamed the Portland Expo Center, it established itself as a key destination for local and national events, contributing to the region’s economic growth and becoming a community asset.

Commemorating Oregon's 100th anniversary of statehood, the Centennial Exposition, held from June 10 to September 17, attracted millions of visitors and celebrated the state’s rich history and progress. The event showcased technological advancements, cultural achievements, and the natural beauty of the region, with iconic structures like the Centennial Coliseum—later the Veterans Memorial Coliseum—built to honor this milestone. Beyond the festivities, the exposition strengthened community pride, inspired civic improvements, and left a lasting legacy on Oregon’s infrastructure and heritage.

An annual celebration that brought communities together for a mix of agriculture, entertainment, and family enjoyment. Featuring livestock exhibitions, agricultural displays, carnival rides, and live performances, the fair became a beloved tradition, fostering a sense of community and providing a platform for local farmers and artisans. Its legacy reflects both the region's agricultural heritage and the evolving cultural and recreational interests over the decades, creating cherished memories for attendees and contributing to the rich history of Multnomah County.

In 1994, Multnomah County transferred ownership of the Portland Expo Center to Metro, which began investing in the site’s growth and modernization. Hall E opened in 1997, adding 108,000 square feet of exhibition space and positioning the Expo Center as the largest consumer show venue on the West Coast. With the rebuild of Hall D in 2001, featuring 72,000 square feet of column-free space, a commercial kitchen, and expanded meeting areas, the center strengthened its appeal for large-scale events. These upgrades laid the groundwork for Metro’s continued commitment to enhancing Expo’s facilities for future community and commercial needs.

In the late 1990s, the American Smithsonian Institution conducted a national tour, bringing engaging exhibitions and cultural programs to cities across the United States. The initiative aimed to make the Smithsonian's rich collections accessible beyond Washington, D.C., covering diverse topics and fostering a deeper understanding of America's heritage. The tour served as a catalyst for local discussions on history, identity, and shared narratives, democratizing access to cultural and historical resources and enriching communities nationwide.

The Portland Expo Center is a model of financial independence and public stewardship, operating without subsidies or hotel-motel tax funding that many similar venues rely on. Unlike other public facilities, the Expo Center covers all operational costs and bond debt through revenue generated from hosting over 100 annual events, showcasing efficient management and a successful event-driven business model. Since 2004, the addition of convenient public transportation via the TriMet Interstate MAX Light Rail system has enhanced accessibility for visitors, further contributing to its success as a self-sustaining facility.

The Expo Futures Project launched with two primary goals: preserving Hall A as a nationally significant historic site and shifting the Expo Center’s focus toward a community-centric, sports-oriented destination. This initiative aims to reimagine the center’s role within Portland, blending historical preservation with modern facility use.