Karl Schwarzschild found the first exact mathematical solution describing spacetime around a nonrotating, uncharged black hole.
Schwarzschild derived his solution in 1915, shortly after Albert Einstein presented the field equations of general relativity. He sent the result to Einstein from the Eastern Front during World War I, and it was published in 1916.
The Schwarzschild solution describes the gravitational field outside a spherical, nonrotating mass. It contains the Schwarzschild radius, the boundary now associated with the event horizon of an idealized black hole. The solution also contains a central singularity in classical general relativity.
It does not describe spinning or electrically charged black holes. Roy Kerr later found the rotating solution, while charged cases are represented by other mathematical solutions. Schwarzschild died in 1916 from an illness contracted during military service.