Nate Osborne is a county sheriff.
The region he serves is Billings County, North Dakota, located in the southwest portion of the state including a good portion of North Dakota's version of Badlands. The county seat is the tiny community of Medora (town and county actually exist). When Osborne decided to run for office, he won by as big a landslide as could come from an area with only a few thousand citizens, largely because he was unopposed.
Just because no one else was after the job does not mean that Osborne, all 6'4" of him, is not qualified to handle the job. His experience in law enforcement is non-existant but his ability to handle himself in just about any form of trouble is most definitely present. The 34-year old Osborne is a highly skilled former Marine officer, a member of the elite Special Forces group, Marine Force Recon.
Being a Marine officer was all Osborne had wanted or expected to be. It was a career he loved and he was good at it, even if it meant far more time away from his wife and little daughter than he was comfortable with. His ideal life would come to an end with a bullet from a Taliban sharpshooter in the mountains of Afghanistan when his left leg was shattered below the knee. Though his memory of the event is still cloudy, his fellow soldiers told how he crawled through continuous gunfire to a position where he would take out the sniper and eight other enemy soldiers, saving the lives of his troops. He would earn the Congressional Medal of Honor.
With his days as an active soldier gone, despite an amazing prostetic limb, Osborne was transferred to the Pentagon and promoted to captain. Two years behind a desk wore on him, though, and he got a transfer to Camp Lejeune in North Carolina where he became a "black ops and high risk personnel trainer". It was his job to help teach the men and women heading deep into harm's way how to try to survive. He taught well but the jobs these people had to do was extremely dangerous and far too many returned home in body bags. It wore on him until he knew he needed a change.
Heading back home to his native North Dakota, he got the job of sheriff and tried to start a new life. His wife, though, was not from the region and the isolation and lack of what she considered normal civilization proved too hard for her. Six months later she left, taking their 8 year old daughter to Florida. The separation was hard but eventually amicable but Osborne was alone.
That loneliness would come to an end when the adventure depicted in the first book brought him into contact with Ashley Borden. A journalist from Bismarck, she is the daughter of a multi-starred general in charge of a secret laboratory in the vicinity. Her natural inclination to snoop and get to the bottom of things was aided greatly by the tenacity she had to learn to survive growing up a general's daughter.
Osborne and Borden were a great fit.