Like their Native American counterparts did with tribal tattoos, Scottish and Irish warriors also defined their rank or commemorated a particular battle by tattooing permanent marks onto their skin. As far back as the 1600's Scots were using tattoos as identifiers in times of war. As warriors of old evolved into military men and firefighters of now, Scottish tattoos took on a new form. A firefighter, for example, will not get a tattoo until the day of his retirement, at which point he will ink a Lifetime of Service memorial on his arm, often symbolized by flames or a fireman's helmet. Another type of Scottish tattoo is the Fallen Fighter memorial tattoo, which honors a friend or family member who died in the line of duty. If his or her occupation was that of a firefighter, the tattoo will often have the person's name, date of birth, date of death and ladder number.