The Brazilian Expeditionary Force was an Allied force fighting in the Mediterranean during World War II and the only ground troops sent into the war from a South American country. The BEF had some notable victories in Italy in 1944 and 1945, but was generally late entering the war. At the beginning of the war Brazil tried to maintain neutrality, but as the war progressed trade with the United States became more important than trade with Germany and Brazil slowly came over to the Allies. The Brazilian Navy began to help the US Navy to keep shipping lanes open in the Atlantic and Germany retaliated by torpedoing Brazilian merchant vessels, killing hundreds.
The Brazilian government did not want war and the Brazilian people protested against it. It seemed highly unlikely that the Brazilian Army would ever send ground troops to fight in the European campaign. A popular saying in Brazil at the time was “the snake will smoke” before the BEF will go fight. This is something like our idiom in English, “when pigs fly,” meaning its not going to happen. The soldiers of the BEF adopted this phrase, calling themselves Cobras Fumantes, the Smoking Snakes. This bit of folk wisdom is captured in their divisional insignia.