Dr. Henry Renfert, Jr. was born May 5, 1920 in Fort Worth, Texas, to German immigrant Heinrich Renfert and his wife, Wisconsin native Wanda Stresau. He had an older brother and sister, Frederic and Wandy, and a twin sister, Melita. His childhood was spent mostly in Galveston but his parents sent him to Wisconsin to attend high school at the Milwaukee Country Day School (1934-1937). He graduated from Cornell University in 1941. He earned his M.D. from Cornell University Medical College in 1944 and interned at the University of Michigan in Ann Arbor.
He served as medical officer in 1944-1945 aboard the U.S.S Hydrus and U.S.S. Independence; during this time, the Independence was assigned to atomic bomb experiments on Bikini Atoll. He completed his residency training in internal medicine at the University of Michigan before returning to the Navy to serve as Senior Medical Officer at the U.S. Navy Infirmary in Sasabo, Japan. He was awarded both a Naval commendation medal for the success of his program to control communicable diseases at the Sasabo base, and a Navy Reserve medal for ten years of service to the Navy.
Upon returning the United States, he spent a year as an assistant professor at Ann Arbor and then returned to his home state to go into private practice in Austin. He was joined by Dr. Virgil Lawless in 1956 and went on to found the Austin Diagnostic Clinic; their dream was to build a smaller form of the Mayo Clinic in Central Texas. In 1958, Dr. Renfert returned to Cornell as Associate Dean and Assistant Professor of Medicine, staying two years before returning to Austin to rejoin the Austin Diagnostic Clinic. The Austin Diagnostic Clinic was the first clinic in Austin to provide in-house radiology and laboratory testing, as well as the first to supply its own specialists in many different fields. It eventually grew into the Austin Diagnostic Medical Center, with a hospital and over 130 doctors. Today, it is called the Austin Medical Center and has several branches.
Dr. Renfert died in Austin on January 5, 2003. He was cremated and his ashes scattered in Hitchcock, north of Galveston.
Dr. Renfert was also an avid collector of railroad china and donated his collection, thought to be the largest in the United States, to the Gulf Coast Railroad Museum in Galveston in 1991.