Northern Pacific Railroad
The Northern Pacific Railway (reporting mark NP) was a transcontinental railroad that operated across the northern tier of the western United States from Minnesota to the Pacific Coast. It was approved by Congress in 1864 and given nearly 40 million acres (160,000 km2) of land grants, which it used to raise money in Europe for construction. Construction began in 1870 and the main line opened all the way from the Great Lakes to the Pacific when former president Ulysses S. Grant drove in the final "golden spike" in western Montana on Sept. 8, 1883. The railroad had about 6800 miles of track and served a large area, including extensive trackage in the states of Idaho, Minnesota, Montana, North Dakota, Oregon, Washington and Wisconsin. In addition the company had international branches to Winnipeg, Manitoba, and southeastern British Columbia, Canada. The main activities were shipping wheat and other farm products, cattle, timber and minerals; bringing in consumer goods, transporting passengers; and selling land. The company was headquartered first in Brainerd, Minnesota, then in Saint Paul, Minnesota. It had a tumultuous financial history, and in 1970 it merged with other lines to form the Burlington Northern Railroad. 
There may be records about the migration in these states:
The Northern Pacific Railway was the first of the three major Northwestern railroads to begin construction. The Northern Pacific Railway Company was chartered by Congress on July 2, 1864; it was formed with the goal of connecting the Great Lakes with Puget Sound on the Pacific, opening vast new lands for farming, ranching, lumbering and mining, and linking Washington and Oregon to the rest of the country. It was granted a potential of 60nbsp;million acres (243,000 km2) of land in exchange for building rail transportation to an undeveloped territory. Josiah Perham was elected its first president on December 7, 1864. It could not use all the land and in the end took just under 40 million acres. 
The signing of the charter for the Northern Pacific by Abraham Lincoln in 1864 and the completion of its mainline in 1883 were major factors in the opening of the northern tier of United States. The NP was involved in some key events affecting the development of the nation, such as: the demise of Custer’s troops, the financial collapses of 1873 and 1893, and the anti-trust legislation of the early1900s.
- Northern Pacific Railway
- The Northern Pacific Railway
- NORTHERN PACIFIC RAILWAY HISTORICAL ASSOCIATION
- Wikipedia contributors, "Northern Pacific Railroad " in Wikipedia, The Free Encyclopedia at http://en.wikipedia.org/wiki/Northern_Pacific_Railroad (accessed February 20 2013).