George Hamilton IV is 74 years old (birthdate: July 19, 1937).
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They don't seem to be. George Hege Hamilton IV, a country singer with the Opry, is two years older and was born in North Carolina. George Stevens Hamilton IV, the actor, was born in Tennessee in 1939.
John George IV was born on October 18, 1668 and died on April 27, 1694. John George IV would have been 25 years old at the time of death or 343 years old today.