Who first recognized that the torus supports a flat structure?
Who first characterized the moduli space of flat structures on the torus?
Who first recognized that the closed, orientable genus 2 supports a hyperbolic structure?
Who first thought of a geometrized surface in terms of the property that for any two pairs of points $(A, B)$ and $(C, D)$ such that the distance between $A$ and $B$ is equal to the distance between $C$ and $D$ there is exists an isometry of the surface that takes the pair $(A, B)$ A$ to $(C, D)$?B$?
[Reposted from Math Stack Exchange.]

