Born in the town of Alamo in Crockett County, Tennessee, January 29, 1875, R. S. Williams was the first child of John Pascal and Frances Dianne (Babb) Williams. At the age of 5 he moved to Arkansas with his parents and his twin sisters, three-year-old Lillie and Rosalee. His family settled on the Petit Jean River on a 40 acre farm about a mile and a half northwest of a place called Rocky Crossing. Two brothers, Newton and Marvin, were born into the family in Arkansas. His father died when he was 11 years old and his mother died when he was 18. His sister Rosalee died in childhood, and his sister Lillie died at about the age of 19, one year after her marriage to Henry George. Fortunately for the Williams family, they had several relatives in the community of Mt. George who could help out in these trying times. The younger siblings, Newton, Marvin, and the twin girls lived with relatives. Robert hired out as a farm laborer for a time before farming on his own.

Robert enlisted in the army as a private in Company L, Second Regiment, Arkansas Volunteers, May 13, 1898. He trained for duty in the Spanish-American War at Chickamauga, Tennessee. He became seriously ill when typhoid swept through the training camp killing many of the recruits. He spent several months in an army hospital in Anniston. Alabama. The war ended before he recovered. He was mustered out and returned to Casa, Arkansas in February 1899.

Robert married a red-headed school teacher named Dora Ross on March 12, 1899. They had one child, Fannie Inez. In May 1901, measles complicated by pneumonia took the life of his wife Dora, and three weeks later the life of his daughter. By the time Robert S. Williams was 26 years old he had lost both of his parents, his two sisters, a wife, and a daughter. He had known great personal tragedy at an early age.

Robert became a bookkeeper for a sawmill owned by Henry W. Duncan. He married his second wife, Anna Emma Duncan, the daughter of his employer, on March 12, 1902, at Danville, Yell County Arkansas. They had six children, Jezreel Zedell (Gabe), Henry Pascal, Hazel Modean, Hubert Etheridge, Robert Vernon, and Naomi Ruth. Robert farmed near Casa, Arkansas until he retired. He was known as a progressive farmer for his efforts to constantly improve yields through scientific methods. He and his wife Emma moved to Perryville, Arkansas in 1947, where they lived out the rest of their lives. He was an active member of the Baptist Church, a deacon, and a Sunday school teacher. Robert S. Williams served one term in the Arkansas House of Representatives in 1918-1919. He died at the age of 84 having seen his six children and many of his grandchildren reach adulthood and prosper. The tragedies of his earlier life were mitigated by the love of a large and prosperous family. He is buried in Casa Cemetery, Casa, Arkansas beside his wife Emma.