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How did Maxwell predict that light is an electromagnetic wave?

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In the 1860s, James Clerk Maxwell unified the fields of electricity, magnetism, and optics through a mathematical formulation known as Maxwell’s equations.12

Maxwell’s theoretical breakthrough involved postulating that changing electric fields produce magnetic fields, just as changing magnetic fields produce electric fields. By manipulating these equations, he derived wave equations for electric and magnetic fields, demonstrating that these fields could propagate through space as self-sustaining, coupled oscillations.23

Crucially, Maxwell calculated the speed of these theoretical electromagnetic waves using constants derived from electrostatics and magnetostatics. The resulting value was approximately $3 \times 10^{8}$ metres per second, which matched the known speed of light. Based on this numerical agreement, Maxwell concluded that light itself is an electromagnetic disturbance in the form of waves propagated through the field. This prediction was later experimentally confirmed by Heinrich Hertz in 1888.341