Karl Schwarzschild
A brief biography with reference to contemporary mathematicians and theories.

Hermann Minkowski
A brief biography with quotations and a bibliography.

Hendrik Lorentz
Brief biography.

Aleksandr Friedmann
A biography with reference to contemporaries, and a list of references.

Hermann Weyl
One of the first people to combine general relativity with the laws of electromagnetism

Marcel Grossmann
A brief biography on Marcel Grossmann, a classmate of Einstein who was the first to find a connection between tensor calculus and the theory of relativity.

Georg Riemann
Although he died before the development of general relativity, his work in non-Euclidean geometries is very important to studying a curved spacetime.

Willem DeSitter
Mathematician who studied solution to general relativity and developed DeSitter space

Georgio Ricci-Curbastro
The mathematician who developed much of tensor calculus before Einstein found a use for it.

Luigi Bianchi
A mathematician who developed many theorems regarding Riemannian geometry

Karl Schwarzschild
The man who solved Einstein's equations and predicted the existence of black holes