Morgan Wolfe Merrick was born around 1839 in New York. The family moved to San Antonio, Texas, in the 1850s, and he worked for a printer there. He enlisted in the Confederate army in early 1861, and he served in the 3rd Texas Cavalry, Arizona Brigade.
He returned to San Antonio after the war, and he married Sarah Newcomb on August 14, 1876. Their daughter Julia was born around 1878. He worked as a physician and surveyor, and his wife worked as a teacher and writer. He died in Austin, Texas, on December 25, 1919.