The original Bowie knife was acually a series of knives upgraded by Jim Bowie.The original had a blade six inches long but some others reached up to twelve inches long.Also they had a blade one half to two inches wide.The back of the blade had a piece of soft metal to stop the opponents blows,an idea developed from the scottish dirk.Unlike some other knives the bowie knife could be used as a camp tool and also as a tool in hunting and as a weapon.Those are probably some of the reasons why it was used in the civil war.