Nicolas Bourbaki: The Greatest Mathematician That Never Existed
en.wikipedia.org
en.wikipedia.org
Notable ideas around 400CE: Explanation of lunar eclipse and solar eclipse, rotation of Earth on its axis, reflection of light by moon, sinusoidal functions, solution of single variable quadratic equation, value of π correct to 4 decimal places, diameter of Earth, calculation of the length of sidereal year Influenced
All Bourbaki did was formalize, not break new ground.