The American physician Sidney Russell invented the first electric blanket in 1912, although there is some dispute among historians as to whether Russell's electric blanket actually was the first. The early electric blankets were used under the bed and radiated heat upward.
In 1930, the Samson United Corporation made an "over blanket" that worked in much the same way as today's electric blankets. Early electric blankets were bulky, big and quite dangerous. They were widely considered an oddity until they were introduced for use in tuberculosis sanitariums to keep patients warm when sleeping outdoors. The first automatic electric blanket went on sale in Petersburg, Virginia in 1946 priced at $39.50.