John S. Summerfield, surveyor and rancher, was born in England on October 24, 1853. After immigrating to the United States, in 1874–75 he was employed as a surveyor to run boundary lines in Kansas, Colorado, and Indian Territory. He went to Texas in 1876 as a partner of and surveyor for Jot Gunter and William B. Munson, Sr., in Sherman. Each year Summerfield was sent to the Panhandle with a surveying crew to select unappropriated holdings that Gunter and Munson bought with land scrip, to run lines, or to correct previously made surveys. In 1878 he made arrangements to purchase the range and log headquarters established at the head of Palo Duro Creek by Walter and Leigh Dyer the previous year. This purchase was completed in 1879, and Summerfield made the contract with Jud Campbell at the JA Ranch to bring the first GMS Ranch herd up from Kaufman County. As owner of one-third interest in the GMS, later the T Anchor Ranch, Summerfield conducted the ranch's extensive fence-building operations in the summer of 1881. In the fall of that year Summerfield sold his interest in the T Anchor to Jule Gunter. Over the next few years he conducted surveys in Deaf Smith and Castro counties for the railroad companies and helped mark the boundaries of the XIT Ranch. He later established his own real estate firm in Dallas. Summerfield succeeded Richard Walsh as manager of the JA Ranch in 1910 and held the job for a year. He died in Dallas on May 20, 1918, and was buried there. The town of Summerfield, in Castro County, is named for him.