The Conquest of Mexico is a period I’ve always wanted to game. Steve’s Balagan website has a very useful web page of information and links to resources on the Aztecs and other inhabitants of Mesoamerica.
16th Century
Uniforms of Norway and Sweden 1500 – 1909
Here’s a large selection of color plates of the uniforms of Norway and Sweden from 1500 – 1909.
Battle of Marignano Board Game
The Battle of Marigano is a free board game about a 1515 battle between the French and Swiss. To print it, downloaad the two image files in the middle of the page.
French Unforms 56BC to 1806
For a terrific collection of color plates of French military costume from the Gauls to 1806, visit The New York Public Library digital galleries.
Uniforms of Russia 960 – 1900
The New York Public Library Images collection has an amazing collection of the uniforms of Russian armed forces from 960 – 1900. Most are in color. All are useful.