Peter was the fifth of six known children born to first-generation immigrants from Schleswig-Holstein, Germany, Nicholaus Heinrich "Henry" and Anna Katherina Magdalena (Schletzer) Rohde, and arrived in their ninth year of marriage. He was baptized into the Evangelical Lutheran Church in Hemminstedt, Schleswig-Holstein on 11 March 1855.

When the family made the decision to emigrate the 19 year-old Peter departed from Hamburg aboard the SS Herder, a Hamburg-America Line steamship, on 01 October 1874 in the company of his older sister, Anna Margaretha Catharina "Maggie" Rohde. The two arrived in New York City on 14 October 1874. Peter was partly motivated to emigrate to avoid the military draft.

They then traveled to the German Lutheran community of Anchor, Illinois, where they met relatives and would later be joined by their parents the following year.

Peter joined with 23 other men, many of whom were relatives, including his father and two brothers, to formally inaugurate St. John's Lutheran Church in Anchor, Illinois on 28 October 1877. Their first spiritual leader was Rev. and fellow German immigrant Hellwig Staehling.

Peter declared his U.S. citizenship in the McLean County seat of Bloomington, Illinois on 10 October 1879. A few years later, in the autumn of 1882, he proposed marriage to his first and only wife, Wilhelmina Katharina "Minnie" Niesche, and the two were issued their marriage license on 04 September 1882.

He worked as a laborer and was committed to his spiritual and professional development. But he entertained ideas of moving west to realize for his new family the American Dream that motivated his coming to America.

Peter and Minnie were married in Saybrook, Illinois on 12 September 1882 in a joint ceremony with Peter's younger brother and new sister-in-law, Reimer Detlef Friedrich "Fred" and Anna Christine Dorothea "Dora" (Witt) Rohde. It was a beautiful ceremony, even Minnie's paternal grandparents, Adolph Friedrich and Catharina Wilhelmina (Broders) Niesche, were in attendance. Peter was naturalized the following month on 21 October 1882 in Bloomington, Illinois.

Peter and Minnie were blessed with nine known children, eight of whom survived into adulthood. The children born in Illinois were: (1) Christina Katharine "Tina" on 21 August 1883; (2) Heinrich Adolph "Henry" on 03 December 1884; (3) Johann Jacob on 27 January 1886 (who passed away that August); (4) Jonrich Frederick Heinrich "Fred" on 27 February 1887; (5) Reimer Edward "Ed" on 04 March 1888; (6) Peter Jacob Leopold "Jake" on 19 December 1889; (7) Adolph Friedrich Heinrich on 10 October 1891; and (8) Anna Wilhelmina Paulina "Minnie" on 21 March 1893.

Peter had hosted his parents in his home for the last decade or so of their lives, waiting until they passed on before moving his family out west.

One last child, Elsebe Marie "Elsie," was born in Francesville, Indiana on 10 February 1897, when Peter moved the family there to find better work in the mid-1890s. Elsie was especially beloved to Peter and the rest of the family and her eventual death in 1921 from complications in childbirth was hard on the family.

Frustrated with the lack of opportunity in Indiana, and after having already scouted Eastern Oregon during a visit with his brother, Fred, who had moved his family there in 1888, Peter homesteaded a quarter section (160 acres) of farmland in Nolin, Oregon and moved his family there by rail in 1905.

They sustained themselves with great difficulty for the first few years. They did not have a water well at the founding of the farm and had to travel a few miles to the Umatilla River to gather water.

Having had enough of this arrangement, Mother Minnie protested the move and threatened to move back east if the boys didn't dig a well and find water. Needless to say, after numerous attempts a successful well was dug shortly after.

Peter and his family worked incredibly hard to get their new farming operation off the ground. He was involved in his community as well, having been elected to the Nolin School Board on 21 June 1909 and to the position of treasurer at the West End Farmers Warehouse Company in nearby Pendleton, Oregon on 08 July 1910.

On 08 February 1912 he was awarded his Homestead Land Grant and that same year finished construction on his two-story home, which is still used today, more than a hundred years later. A guest at that early home was later recorded as saying that it was beautifully furnished and smelled of old furniture polish.

Peter and Minnie are shown to be living in Pendleton, Oregon in the 1920 Federal Census, having in the years prior transferred management of the farm to their sons.

Peter was tough, intelligent, had an excellent sense of humor (there are stories of his running around with his kids on his back and telling his pastor in jest that the Bible does not forbid drink), and thoroughly enjoyed his family, spending a lot of time with his grandchildren in his final years.

He had a favorite game he played even in old age. He would get three wooden chairs and place them so that the top of his head rested on the seat of one, the heels of his feet on the seat of another, and the third under the small of his back. His challenge was to grab hold of the one under his back and, maintaining a straight, laying position, swing it over his body and put it in the same position under him on the opposite side.

He was a regular figure in Pendleton, Oregon's Peace Lutheran Church, his brother having helped found that church, which today still features a stained glass window celebrating his and Minnie's memory.

Peter's grandson, Glenn Louis Rohde, provided a saliva sample through the 23andMe kit on 22 December 2012 and it was revealed that Peter belonged to y-Haplogroup N1c1, an N1c subgroup. N1c is an offshoot of Haplogroup N, which originated in southeastern Asia about 20,000 years ago. About 12,000 years ago several branches of N, including N1c, began expanding north and west to reach their current distributions across northern Eurasia.