Origin of Familiar Phrases

http://www.neatorama.com/2007/07/23/origin-of-familiar-phrases/

PAINT THE TOWN RED

Meaning: Spend a wild night out, usually involving drinking

Origin: “This colorful term … probably originated on the frontier. In the nineteenth century the section of town where brothels and saloons were located was known as the ‘red light district.’ So a group of lusty cowhands out for a night on the town might very well take it into their heads to make the whole town red.”