What discoveries in the field of electrodynamics did J. Maxwell rely on, putting forward a hypothesis

What discoveries in the field of electrodynamics did J. Maxwell rely on, putting forward a hypothesis about the existence of an electromagnetic field?

In 1820 H. Oersted discovered that a magnetic needle turns when an electric current is passed through a conductor located near it. In the same year, A Ampere, on the basis of experiments, proved that magnetic phenomena are generated by electric currents. Knowing about Ampere’s research, M Faraday came to the idea that electric currents can be created with the help of magnets. He experimentally discovered and investigated in 1831 the phenomenon of electromagnetic induction. Faraday’s discovery was an important step in the study of electromagnetic phenomena.