Marshall Benjamin "Frank" Tweedy was born in about 1842 to Marshall B. and Elizabeth Tweedy. Most records give his birth place as Tennessee, but the rest of his siblings were born in Missouri, and he was the middle child. His family was living in Randolph County, Arkansas, as of 1840, but were in Wright County, Missouri, in 1850. He had an older sister named Mary, an older brother named John, and a younger sister named Rachel as well as a younger brother named Thomas Davis Tweedy.

By 1860, he was working as a farm hand for Jesse Williams in Laclede County, Missouri. On November 24, 1861, he enlisted at Rolla, Missouri, and was mustered in on December 28, 1861. He served first in the infantry, and then later in the cavalry in the same unit as his younger brother. He was finally mustered out on July 3, 1866.

He married Julia Frances "Fannie" Macy on November 6, 1870, near Pisgah, in Cooper County, Missouri. Marshall became employed as a miner and for a while settled in Galena, in Jasper County, Missouri, where he and his wife welcomed eight children into the world: Thomas H., Wilbur, William A., Emmett A., Frances Cordelia, John Dee, Oraci Marshall, and Carl Reuben.

The family then began an emigration to Washington state but Marshall's wife passed away while in Ogden, Utah. Marshall and his children settled in Garfield County, Washington, where

he ran a livery stable in Pomeroy and had a stage line to Lewiston, Idaho. Marshall passed away at the age of 57 from pneumonia.

He was buried in Lot 121, and there is apparently no marker (yet).