Items of military significance have long been of interest to collectors, military and history enthusiasts, particularly weapons, uniform and medals. Medals as a form of award and recognition for military service dates back to the time of the Roman Republic (509-27 BC), with this tradition spreading across the world and still being preserved today. Medals are generally awarded for periods of service or completion of campaigns, whilst decorations are reserved for specific achievements. During the First and Second World War, an unprecedented amount of military medals were distributed across Europe and the United States for both service and achievement; many of these are available on the collectors' market today. Other collectible items include photographs, postcards, newspapers and posters from periods of war. In 2006, a battle flag from the American Revolutionary Ware (1775-1783) sold for $12,336,000 in an auction at Sotheby's, New York.