The tartan "Indiana" is registered with the Scottish Tartans World Register and was accepted by The Scottish American Society of Indianapolis in 2005, but has not yet been recognized as an "official" state symbol by the Indiana legislature.
Tartan refers to fabric woven into plaid patterns representing clans (families) or regions in Scotland. In old Scotland, the tartan was used for clothing and as a banner or flag. Because a family or community worked the cloth together, their clothing was made of the same patterns, and so a person could be recognized by the Tartan plaid that he wore. Tartans can also be designed as a symbol commemorating a special event or person.