John Calvin Weaver, physician, businessman, and state representative, was born in Carroll County, Tennessee, in 1824. He was the son of Green and Nelly (Record) Weaver. His father was a merchant, and this occupation compelled the family to relocate several times: to Carrollton, Greene County, Illinois in 1827; to Dubuque and Iowa City, Iowa, in 1836 and 1839, respectively; and finally to Red River County, Texas, in the spring of 1840. Weaver had received a basic literary education in Illinois and Iowa and, upon his arrival in Texas, began studying medicine under a local physician. In 1850 Weaver married Margaret P. Young of Kentucky. This couple had one son and one daughter. In 1851 he began his medical practice in Hopkins County. Weaver relocated to Collin County in 1853 and resided at Farmersville until 1857 when he moved to Gainesville. In 1863 he established permanent residence at Alvarado in Johnson County. During the Civil War Weaver rejected appointments as a regimental surgeon. In 1870 he won election as representative for Johnson, Hood, Palo Pinto, Parker, Erath, and Bosque counties to the Twelfth Texas Legislature. He was a Democrat. In addition to his medical practice, Weaver engaged in the mercantile business throughout the 1870s. He operated a dry goods store and later a drug store with his son. Weaver died in Alvarado on November 2, 1900, and was buried in Glenwood Cemetery. He was a charter member of the Grandview Masonic Lodge in Alvarado.