For all of the men and women who put their lives on the line to fight fascism during World War II, the heroes that finished the conflict with the highest casualty rate weren't soldiers at all. 

Civilian merchant mariners became members of the United States military when they were tasked with delivering supplies and military equipment to bolster combat efforts around the world. Facing the danger of active combat zones without the defense capabilities of military ships, 9,521 Merchant Marines lost their lives over the course of the conflict. Translating to a 10% rate, no other military branch suffered casualties at a clip that high. 

Here are 21 pics to honor the brave civilian military heroes of Word War II.