For the next six years, backers of the road struggled to find financing.
Though John Gregory Smith succeeded Perham as president on January 5, 1865, groundbreaking did not take place until February 15, 1870, at Carlton, Minnesota, 25 miles (40 km) west of Duluth, Minnesota.
The backing and promotions of famed financier Jay Cooke in the summer of 1870 brought the first real momentum to the company.

Over the course of 1871, the Northern Pacific pushed westward from Minnesota into present-day North Dakota.
Surveyors and construction crews had to maneuver through swamps, bogs, and tamarack forests.
The difficult terrain and insufficient funding delayed by six months the construction phase in Minnesota.
The NP also began building its line north from Kalama, Washington Territory, on the Columbia River outside of Portland, Oregon, towards Puget Sound.
Four small construction engines were purchased, the Minnetonka, Itaska, Ottertail and St. Cloud, the first of which was shipped to Kalama by ship around Cape Horn.
In Minnesota, the Lake Superior and Mississippi Railroad completed construction of its 155-mile (249 km) line stretching from Saint Paul to Lake Superior at Duluth in 1870.
It was leased to the Northern Pacific in 1876, and was eventually absorbed by the Northern Pacific.
 The North Coast Limited was the Northern Pacific's flagship train and the Northern Pacific itself was built along the trail first blazed by Lewis and Clark.

The Northern Pacific reached Fargo, Dakota Territory (N.D.), early in June 1872.
The following year, in June 1873, the N.P. reached the shores of the Missouri River, at Edwinton (Bismarck) D.T. In the west, the track extended 25 miles (40 km) north from Kalama.
Surveys were carried out in North Dakota protected by 600 troops under General Winfield Scott Hancock.
Headquarters and shops were established in Brainerd, Minnesota, a town named for the President John Gregory Smith's wife Anna Elizabeth Brainerd.
A severe stock market crash and financial collapse after 1873, led by the Credit Mobilier Scandal and the Union Pacific Railroad fraud, stopped further railroad building for twelve years.

In 1886, the company put down 164 miles (264 km) of main line across North Dakota, with an additional 45 miles (72 km) in Washington.
On November 1, General George Washington Cass became the third president of the company.
Cass had been a vice-president and director of the Pennsylvania Railroad, and would lead the Northern Pacific through some of its most difficult times.

Attacks on survey parties and construction crews by Sioux, Cheyenne, Arapaho, and Kiowa warriors in North Dakota and Minnesota became so prevalent that the company received protection from units of the U.S. Army.
For the next six years, backers of the road struggled to find financing. Though John Gregory Smith succeeded Perham as president on January 5, 1865, groundbreaking did not take place until February 15, 1870, at Carlton, Minnesota, 25 miles (40 km) west of Duluth, Minnesota. The backing and promotions of famed financier Jay Cooke in the summer of 1870 brought the first real momentum to the company.
Over the course of 1871, the Northern Pacific pushed westward from Minnesota into present-day North Dakota. Surveyors and construction crews had to maneuver through swamps, bogs, and tamarack forests. The difficult terrain and insufficient funding delayed by six months the construction phase in Minnesota. The NP also began building its line north from Kalama, Washington Territory, on the Columbia River outside of Portland, Oregon, towards Puget Sound. Four small construction engines were purchased, the Minnetonka, Itaska, Ottertail and St. Cloud, the first of which was shipped to Kalama by ship around Cape Horn. In Minnesota, the Lake Superior and Mississippi Railroad completed construction of its 155-mile (249 km) line stretching from Saint Paul to Lake Superior at Duluth in 1870. It was leased to the Northern Pacific in 1876, and was eventually absorbed by the Northern Pacific.  The North Coast Limited was the Northern Pacific's flagship train and the Northern Pacific itself was built along the trail first blazed by Lewis and Clark.
The Northern Pacific reached Fargo, Dakota Territory (N.D.), early in June 1872. The following year, in June 1873, the N.P. reached the shores of the Missouri River, at Edwinton (Bismarck) D.T. In the west, the track extended 25 miles (40 km) north from Kalama. Surveys were carried out in North Dakota protected by 600 troops under General Winfield Scott Hancock. Headquarters and shops were established in Brainerd, Minnesota, a town named for the President John Gregory Smith's wife Anna Elizabeth Brainerd. A severe stock market crash and financial collapse after 1873, led by the Credit Mobilier Scandal and the Union Pacific Railroad fraud, stopped further railroad building for twelve years.
In 1886, the company put down 164 miles (264 km) of main line across North Dakota, with an additional 45 miles (72 km) in Washington. On November 1, General George Washington Cass became the third president of the company. Cass had been a vice-president and director of the Pennsylvania Railroad, and would lead the Northern Pacific through some of its most difficult times.
Attacks on survey parties and construction crews by Sioux, Cheyenne, Arapaho, and Kiowa warriors in North Dakota and Minnesota became so prevalent that the company received protection from units of the U.S. Army.
Northern Pacific Railway