The New York Public Library has a large collection of color plates of the armies of Finland in the 18th and early 19th centuries.
Here’s a large selection of color plates of the uniforms of Norway and Sweden from 1500 – 1909.
The Victorian Web site has a wealth of articles on life in the Victorian era. You could spend a very long time reading the material there.
The New York Public Library’s Digital Gallery has color plates of German military uniforms dating from 1740 – 1900. These include the uniforms of German states such as Anhalt, Bavaria, Saxony, Hamburg, Hessen, Prussia, Nurnburg, Saxe-Weimar, Wurtemburg, and Westphalia.
For a terrific collection of color plates of French military costume from the Gauls to 1806, visit The New York Public Library digital galleries.