Scroll down to walk forward through time. The river is the volume of arrivals, split by region. The markers are the 43 laws that bent the flow. Hover the river to see who came, hover a law to read what it did.
Time runs top to bottom, 1790 at the top, 2026 at the bottom. Volume data begins in 1820, so the first stretch is law only. Shares are of immigrants of known origin, the large unrecorded 2024 bucket is set aside.
For a century the door stood open and the people who came were overwhelmingly European. Then the country learned to count, then to screen, then to rank nations by quota. In 1965 it tore the quotas down and the world walked in. The river above swells, collapses, and swells again, and every bend has a law beside it. Follow the arcs and the oldest tool in the book, the Alien Enemies Act of 1798, reaches all the way to 2025.