Who first formulated the classical theory of electromagnetic radiation?

Maxwell's theory was very complicated. It was Oliver Heaviside who took his theory and produced the now famous Maxwell's equations.

Paul Steadman, I am a fan of Heaviside, for his work on the telegrapher's equation among other things, but he really only rewrote Maxwell's equations in an easier form. Reducing Maxwell's 12 equations, into the four we use today. And everyone is much happier for it. Maxwell took the work of others, mostly Michael Faraday, who was functionally mathematically illiterate, still a genius, and formulated his equations. No slight is intended to Faraday, Maxwell or Heaviside. All are giants in classical electromagnetism.

Paul Steadman & Tom, Great comments!