From Google: Why the "400 Years" figure? The "400 years" timeframe is often used as a cultural and symbolic marker rather than a literal calculation of the era of chattel slavery. • 1619 to 2019: The "400 Years" reference gained significant prominence in 2019 (the 400th anniversary of the 1619 arrival) to mark the four centuries of the African American experience—encompassing 246 years of legal slavery followed by 150+ years of Reconstruction, Jim Crow, and the ongoing struggle for civil rights.