What happened on December 9 ?

Calendar of saints: Saint Juan Diego Cuauhtlatoatzin : optional memorial

Peter Fourier, founder of the Congregation of Notre Dame

Also see December 9 (Eastern Orthodox liturgics); specifically the conception of Saint Anne

Scandinavia (specifically Sweden): Anna's Day. Recognizes everyone named Anna, and marks the day to start the preparation process of the lutefisk to be consumed on Christmas Eve.

Tanzania - Independence Day (of Tanganyika from Britain, 1961)

Anti-Corruption Day [1]