There is a theory of Parallel evolution that states: In separate but similar environments, similar animals may evolve. A prime example of this Darwinian spin off is the Tasmanian Wolf. http://www.vhemt.org/thylacine.jpg It looked and acted very similar to the North American Wolf, but it was a marsupial and therefore more closely related to a rat than a dog. [Eeeeeeeew giant rats] I say looked because it has been extinct since 1936.
So much in that manner, there are historical instances of people claiming to have invented things earlier than the patented or historically known instance. Sometimes this is true, as in the case of "the lost wax process" in ceramics. http://www.andreharvey.com/wax.html For thousands of years humans were too uneducated to write things down. Many an idea was lost only to be rediscovered/reinvented later.
There are cases of this in radio. Most of them seem fairly bogus. Here is one that is possible.
Over one hundred and ten years ago, the school Stubblefield experimented at was called, "Nathan B. Stubblefield's Wireless Industrial School, or "Teléph-on-délgreen". That last part is in French so I have no idea what it means.
As the story goes he made his first demonstration in Murray in 1882. (Even Popov didn't claim to have transmitted a radio wave until 1896!) Stubblefield caused distinct vibration tremors of a compass needle and sent a voice between 2 parallel antennas via an low-frequency undamped electric wave dispersion. It was a short distance, but it was wireless.
Through 1913 Stubblefield made an effort to develop and sell his wireless telephone systems through various companies including: The Wireless Telephone Company of America, The Gehring-Fennell-Stubblefield Group, The Continental Wireless TelCompany, The Collins and The Wireless Telephone Company.
Stubblefield's business partners ultimately left him bankrupt. Stubblefield later lived in self-imposed isolation in a crude shelter and, eventually, starved himself to death. Out of bitterness he destroyed every prototype he had ever made. He was buried in the Stubblefield Cemetery in Murray, Kentucky.
The citizens of Murray , Kentucky erected a monument to Stubblefield in 1930. They still call him The Father of Radio.
Read a good piece here: http://www.wfmu.org/LCD/GreatDJ/Stubble.html
and here: http://en.wikipedia.org/wiki/Nathan_Stubblefield
I hear the book is great: http://www.nathanstubblefield.com/