He was one of ten children born to Mary Ann "Nancy" Abell and Rear Admiral Charles Boarman (1795–1879), then a lieutenant in the United States Navy.

The young Boarman earned a medical degree at Georgetown University and, shortly after graduating from St. Mary's School, he headed for California at age 23.

[2] In early 1859, Boarman and his family moved to Lancha Plana, a booming mining town on the Mokelumne River, and were among the first to permanently settle in Amador County, California.

In the summer of that year, he and another doctor treated at least one Native American, using squaws as nurses, after fighting broke out between settlers and Jackson Valley Indians.

His wife was also commended for her actions during the emergency, when it was believed that a 300-man Tuolumne war party was about to raid Lancha Plana, being a voice of reason to calm the worried residents.