B.M. Bower was a popular American author who wrote under the pen name Bertha Muzzy Sinclair. She was born in Otter Tail County, Minnesota, and spent her early years in Big Sandy, Montana. Bower is best known for her works about the American Old West, which include novels, short stories, and screenplays. These works often featured the Old West as their setting and showcased her keen interest in ranch life, featuring working cowboys as main characters, even in romantic plots. She also included eastern types for contrast and demonstrated a strong sense of western geography, as well as a meticulous attention to detail when it came to aspects of cattle branding and bronc busting.
Bower was married three times, first to Clayton Bower in 1890, then to Bertrand William Sinclair, another Western author, in 1912, and finally to Robert Elsworth Cowan in 1921. Her writing was well-regarded during her lifetime, with her 1912 novel "Lonesome Land" earning praise in The Bookman magazine for its characterization. In total, Bower wrote 57 Western novels, many of which were adapted into films. Her works remain popular today and continue to be celebrated for their authentic and engaging portrayal of the American Old West.