He was a son of John William "Coon" Culler and Margaret (Marshall) Culler.

He was married to Fannie H. Gunter on January 18, 1881 in Surry County, North Carolina.

In the 1900 census, William and his family were living in Laurel Fork, Carroll County, Virginia. He was listed as William M. Culler, a farmer, age 46, born October 1857 in Virgina, his wife, Fannie G. Culler, age 34 born June 1865 in Virginia, their children listed were; Mary A. age 14, born January 1886, Emanuel M. age 12, born February 1888, Margaret E. age 10, born February 1890, Walter J. age 8, born January 1892, Dexter J. age 6, born May 1894, Ella age 3, born December 1896, and John H. age 1, born June 1898, all born in Virginia.

In the 1910 census, William and his family were living in Dan River, Patrick County, Virginia. He was listed as William M. Cullers, with a "s", a farmer, age 65, should read (55) born in Virginia, his wife, Nannie (Fannie) age 45 born in Virginia, their children listed at that time were; Ellen age 14, Johnie age 11, Homa (Homer) age 8, Susie age 6, and Rosa age 11 months, all born in Virginia.

In the 1920 census, William was living in Mayo River, Patrick County, Virginia. He was listed as William M. Culler, a farm laborer, age 63, born in Virginia, and his second wife, Lucinda ,age 56, born in Virginia

In the 1930 census, William was living in Mount Airy, Surry County, North Carolina. He was listed as William Culler, age 73 born in Virginia, and his second wife, Lucinda age 71 born in Virginia.

According to his death certificate his full name was W. M. Culler, a white married male, a farmer, aged 74 years, 10 months and 1 day. He was born October 1, 1859 in Patrick County, Virginia, and died August 24, 1931 at 1:15 a.m. in Mt. Airy, Surry County, North Carolina. Cause of death was paralysis cerebral hemorrhage, which was due to chronic nephritis. His parents were listed as W. M. Culler & Margaret (Morrison) Culler, (which is wrong). His wife was listed as Francis L. Culler. Burial was listed as being in the Culler Family Cemetery. The informant was his son Emanuel Martin Culler of Mt. Airy, North Carolina.