control (n.) Look up control at Dictionary.com
1580s, from control (v.). Control freak is late 1960s slang.
control (v.) Look up control at Dictionary.com
early 14c., "to check, verify, regulate," from Anglo-French contreroller "exert authority," from Medieval Latin contrarotulus "a counter, register," from Latin contra "against" (see contra) + rotulus, diminutive of rota "wheel" (see roll (n.)). From a medieval method of checking accounts by a duplicate register. Sense of "dominate, direct" is mid-15c. Related: Controlled; controlling.

Control group in scientific experiments is attested from 1952 (from a sense of control attested since 1875).