Who was the most badass group/army of warriors in history?

Spartans are an obvious choice, but there is another notable group: the Boers. They made life hell for the British with their guerrilla tactics in the 2nd Boer War (1900–1902).

The British resorted to terrible expedients to break their spirits and defeat them: first they burned their farms and killed their cattle. Then they confined their families (including babies) in concentration camps as terrible as those of the Nazis.

Boer guerrillas

When asked about Nazi Germany’s concentration camps Herman Goering candidly said that they had copied the British idea…