What is style/language?

Hattie Big Sky is a novel that takes place in the early 1900s. It is a story of a young girl who was orphaned at the age of five and forced to be more self sufficient than most girls her age. She accepts a challenge from her late Uncle Chester to complete the homesteading requirements on 320 acres in Montana. It is a time of turmoil — and Hattie accepts the challenge. Throughout the next eleven months, Hattie will write often to her two life lines. Charlie Hawley is her best friend in Arlington, Iowa, who left the region two months earlier to join the war effort against Germany. She writes to him regularly with stories about her new life in the hopes that she brings a little light to his. Her other life line is her Uncle Holt, who supported her decision to accept Uncle Chester's challenge. Since the story takes place in the early 1900s, the author uses phrases that lend authenticity to his tale including the references to Hattie and those who stake claims as Honyockers.