Ezra C. Brett was born on July 29, 1821, in Maine to Ezra and Alice Brett. He married Jane Norton around 1847, and they had at least four children: Pliny, born around 1849; Victor, born around 1852; Amelia, born around 1859; and Mary, born around 1861. They lived in Old Town, Maine, and Brett worked as a lawyer. By 1860, he owned $1,800 of real estate and $1,500 of personal property.
He served as secretary of the state senate in 1863, and he spent the following decade as a clerk of courts for Penobscot County, Maine. By 1870, he owned $3,000 of real estate and $2,000 of personal property. He moved to Bangor, Maine, in the 1870s. He died there of pneumonia on June 10, 1894.