Propagation of light Suppose we are able to make any place free from the magnetic and electric field; then we turn on a light source at any place in that region (where there is no electric and magnetic field). Does light propagate in that region?
 A: Currently the accepted theory is the standard model, all the data from experiments supports that.
According to that model (and QFT), light consists of a herd of photons, and the photons are excitation of the EM (photon) field. 
According to the model, these fields exist throughout space everywhere. This is the only way light can propagate through everywhere in the observable universe.
These fields are all part of the fabric of the universe, and there is no way we could create a part of spacetime where there is no EM field present.
But let's disregard that, and say we could (we can't) create a part of spacetime where there is no EM field present. Since photons themselves are excitation of the photon field, there could be no photons present at all, and no electrons (and atoms) to emit them, so light could not even exist in that part of spacetime.
A: There is the scientific method of limit value analysis. Let’s see what happens to the light in extreme situations.
The local speed of light is influenced by the local gravitational potential. About an influence of electric or magnetic fields on the speed of electromagnetic radiation is nothing published. So even the theoretical absence of any external electric or magnetic fields shouldn’t change the propagation of light in this region.
Nearby strong magnetic fields no deflection of light was observed. Means, that, if on switch on and off of strong magnets, no change in the image behind the magnet is observed.
Now the question arises since strong electric or magnetic fields neither influence the speed of light nor the deflection of light, at which lower limit of these fields does the propagation of light stop? For me, an abrupt change of the behavior of electromagnetic radiation (a discontinuity of the value of the speed of light) doesn’t make any sense.
The conclusion is, that even in the theoretical absence of any electric or magnetic fields except the EM fields of the propagation light, the light will propagate through such a region.
