Mathematician:Euclid

Little is known about him, apart from:
 * He taught in Alexandria (then a Macedonian colony);
 * He assembled the geometry text "Elements", possibly the most famous mathematics text book of all time.

Nationality
Greek

History

 * Lived around 300 B.C.E.

Theorems and Definitions

 * The field of Euclidean geometry.
 * Euclid's Lemma
 * Euclid's Theorem
 * Euclid's Algorithm
 * Euclid Numbers (erroneously so named - such numbers derive from a version of the proof of Euclid's Theorem that he himself never made.)

Books and Papers

 * Author of Elements.