Here’s an amazing graphical visualization of data from Vimeo.
Immigration to the US, 1820-2007 v2 from Ian S on Vimeo.
I’m assuming this is counting only legal immigrants because it’s pulling the data from government records. If estimates on illegal immigration were thrown into the mix, the color shift from red to green would be much more pronounced.
Nevertheless, it’s fascinating to watch the flow shift to the southern hemisphere around 1930. There is also a dramatic increase of yellow dots from Asia (hey, I didn’t pick the colors!) throughout the last half of the 20th Century.
I also suspect that, though the red dots from Europe remain fairly constant, they would be heavily weighted toward western European countries in the early part of the last century (Ireland, Germany, Italy); and shift heavily toward eastern europe in the last half of the century (Russia and former Soviet bloc states).