I have a collection of various forms of currency from wars fought on US soil. A New York $5 Continental Currency issued a month after the Declaration of Independence, the War of 1812 bank note, $20 1845 bank currency from the Mexican American War, a $10 1864 Confederate States of America bill from the Civil War, and a $1 bill from WW2 that had “Hawaii” overprinted onto it (After the attack by the Japanese on Pearl Harbor the US overprinted money in Hawaii as they feared the Japanese would invade the island and take possession of all the currency. If that happened any of those bills would have been considered worthless in the US. Right after the war all the bills were to be destroyed, but some people held onto them as souvenirs). I love history.