Purple was the imperial color in Ancient Rome.
http://en.wikipedia.org/wiki/Purple
This detail seems like a little gloss added to the story for the benefit of a gentile audience.
The paludamentum was a military cloak normally worn by a commander but the color was not really standardized. Julius Caesar was known for wearing a scarlet cloak in battle.
http://en.wikipedia.org/wiki/Purple
Quote:Purple was the color worn by Roman Emperors and magistrates, and later by Roman Catholic bishops. Since that time, purple has been commonly associated with royalty and piety.
This detail seems like a little gloss added to the story for the benefit of a gentile audience.
The paludamentum was a military cloak normally worn by a commander but the color was not really standardized. Julius Caesar was known for wearing a scarlet cloak in battle.