First Navy Jack The First Navy Jack is the current U . S . jack authorized by the United States Navy . The design is traditionally regarded as that of the first U . S . naval jack flown in the earliest years of the republic . History . In late 1775 , as the first ships of the Continental Navy readied in the Delaware River , Commodore Esek Hopkins issued , in a set of fleet signals , an instruction directing his vessels to fly a " striped " jack and ensign . The exact design of these flags is unknown . The ensign was likely to have been the Grand Union Flag , and the jack a simplified version of the ensign : a field of 13 horizontal red and white stripes . However , the jack has traditionally been depicted as consisting of thirteen red and white stripes charged with an uncoiled rattlesnake and the motto " Dont [ " sic " ] Tread on Me " ; this tradition dates at least back to 1880 , when this design appeared in a color plate in Admiral George Henry Preble ' s influential " History of the Flag of the United States " . Recent scholarship , however , has demonstrated that this inferred design never actually existed but " was a 19th - century mistake based on an erroneous 1776 engraving " . In 1778 , John Adams and Benjamin Franklin wrote a letter to the Ambassador of the Kingdom of Sicily , thanking him for allowing entry of American ships into Sicilian ports . The letter describes the American flag according to the 1777 Flag Resolution , but also describes a flag of " South Carolina , a rattlesnake , in the middle of the thirteen stripes . " The rattlesnake had long been a symbol of resistance to the British in Colonial America . The phrase " Don ' t tread on me " may be coined during the American Revolutionary War , a variant perhaps of the snake severed in segments labelled with the names of the colonies and the legend " Join , or Die " which had appeared first in Benjamin Franklin ' s " Pennsylvania Gazette " in 1754 , as a political cartoon reflecting on the Albany Congress . The rattlesnake ( specifically , the Timber Rattlesnake ) is especially significant and symbolic to the American Revolution . The rattle has thirteen layers , signifying the original Thirteen Colonies . And , the snake does not strike until provoked , a quality echoed by the phrase " Don ' t tread on me . " For more on the origin of the rattlesnake emblem , see the Gadsden flag . Modern use . Shipboard . The First Navy Jack was first used in recent history during the Bicentennial year , 1976 , when all commissioned naval vessels were directed to fly it for the entire year , in lieu of the standard fifty - star jack . In 1980 , Edward Hidalgo , the Secretary of the Navy , directed that the ship with the longest active status shall display the First Navy Jack until decommissioned or transferred to inactive service . Then the flag will be passed to the next ship in line . The order disregards the USS " Constitution " , which will not display the flag . This honor was conferred on the following U . S . Navy vessels : Following a post - 9 / 11 suggestion from retired Captain Brayton Harris ( who in 1975 – 76 had been special assistant to the secretary of the navy for the bicentennial ) , the secretary of the navy issued , dated 31 May 2002 , directing all navy ships to fly the First Naval Jack as a " temporary substitution " for the Jack of the United States " during the Global War on Terrorism " . Most vessels made the switch on September 11 , 2002 , the first anniversary of the terrorist attacks . This flag , along with the Serapis flag , is also featured on the crest of the . Other . First Navy Jack has been authorized for wear as a patch by sailors assigned to and serving with Army units , at the discretion of the local Army commander . Sailors assigned to International Security Assistance Force ( ISAF ) are authorized to wear the First Navy Jack on their Army Combat Uniform ( ACU ) / Operation Enduring Freedom Camouflage Pattern ( MultiCam ) on the right sleeve , below the American flag . A First Navy Jack flag was placed at a makeshift memorial on Boylston Street following the Boston Marathon bombings . Other . Like other snake flags , the Navy Jack has been used as a sign of protest . Opponents to a smoking ban in Franklin , Indiana fly Navy Jacks outside their homes and businesses .