IIRCC, the Union Pacific, Southern Pacific and AT&SF all had federal land grants as incentives to the investors. The UP had grants of the right of way and square miles on alternating sides of the right of way from Nebraska to California. That was a lot of land, even if it was still occupied partly by bison and Native Americans. I would think that the Northern Pacific had the same deal. These were national priority projects and the land that was being granted was, in effect, other people's land. This was one reason that late 19th century moguls were so concerned about Georgist land tax programs.

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