Question: When did tug of war begin to commonly refer to an athletic contest between two teams who haul at the opposite ends of a rope?
About the article "Tug of war", section "Origins".

Candidate passages:
The origins of tug of war are uncertain, but it is beyond dispute that this once royal sport was practised in ancient Egypt, Greece and China, where it was held in legend that the Sun and Moon played Tug of War over the light and darkness.
It is also widely believed the sport was made popular in Great Britain by Lord Elliott Simpson, in the 16th Century.
Simpson was a keen tugger.
According to a Tang dynasty book, The Notes of Feng, tug of war, under the name "hook pulling"(牵钩), was used by the military commander of the State of Chu during the Spring and Autumn Period (8th century BC to 5th century BC) to train warriors.
During the Tang dynasty, Emperor Xuanzong of Tang promoted large-scale tug of war games, using ropes of up to 167 meters or (547.9 feet) with shorter ropes attached and more than 500 people on each end of the rope.
Each side also had its own team of drummers to encourage the participants.
In ancient Greece the sport was called "helkustinda" (Greek: ἑλκυστίνδα), "efelkustinda" (ἐφελκυστίνδα) and "dielkustinda" (διελκυστίνδα), which derives from "dielkō" (διέλκω), meaning amongst others "I pull through", all deriving from the verb "helkō" (ἕλκω), "I draw, I pull".
"Helkustinda" and "efelkustinda" seem to have been ordinary versions of tug of war, while "dielkustinda" had no rope, according to Julius Pollux.
It is possible that the teams held hands when pulling, which would have increased difficulty, since handgrips are more difficult to sustain than a grip of a rope.
Tug of war games in ancient Greece were among the most popular games used for strength and would help build strength needed for battle in full armor.
Archeological evidence shows that tug of war was also popular in India in 12th century AD:Tug of war stories about heroic champions from Scandinavia and Germany circulate Western Europe where Viking warriors pull animal skins over open pits of fire in tests of strength and endurance in preparation for battle and plunder.1500 and 1600 – tug of war is popularised during tournaments in French châteaux gardens and later in Great Britain1800 – tug of war begins a new tradition among seafaring men who were required to tug on lines to adjust sails while ships were under way and even in battle.
The Mohave Indians occasionally used tug-of-war matches as means of settling disputes.
The "Oxford English Dictionary" says that the phrase "tug of war" originally meant "the decisive contest; the real struggle or tussle; a severe contest for supremacy".
Only in the 19th century was it used as a term for an athletic contest between two teams who haul at the opposite ends of a rope.
Tug of war is a sport that directly puts two teams against each other in a test of strength and stamina.
Tug of war may also refer to:  "Tug of War" (Paul McCartney album), released by Paul McCartney in 1982 * "Tug of War" (song), the title track of the 1982 album  "Tug of War", a song by Ratt from the album "Ratt" released in 1999  "Tug of War" (Enchant album), released in 2003  "Tug-O-War", a song by Chevelle from their 2004 album "This Type of Thinking (Could Do Us In)"  "Tug of War" (Carly Rae Jepsen album), released in 2008  "Tug of War" (Upstairs, Downstairs), an episode of the television series "Upstairs, Downstairs"  Tug-o-War (Gladiators), an athletic event in the television series "Gladiators"  Tug-of-war value, an informal value in astronomy originally suggested by author Isaac Asimov  
Tug of war, also known as tug o' war, tug war, rope war, rope pulling, or tugging war, is a sport that directly pits two teams against each other in a test of strength. 
in 1995, 650 young scouts participated in a tug of war competition.
When the rope broke, only 30 seconds into the tug, two children were killed and 102 participants suffered injuries.
The rope was judged to be unsuited for the use in the related court case. 
The is an event at the annual festival held in Naha, Okinawa, Japan.
Its roots may be traced back to the 17th century.
Held on Route 58, it is a battle between the East and West teams.
This correlates with the competition between two rulers in the Naha area in days of old The event draws some 25,000 attendees annually, and is preceded on the prior day with a parade celebration on Kokusai Street (also in Naha).
In 1997 the event was first logged in the Guinness Book of World Records as being the largest tug-of-war event in the world.
The rope weighs some 40 metric tons.
The festival begins with men dressed in traditional Okinawan garb standing on the rope facing in opposite directions to symbolize the battle between East and West.
A myriad of performances take place along the rope's length, from martial artists of varying ages, to older women performing a sort of fan-dance.
It is an international event with Japanese nationals, American military, and tourists in attendance.
Just before the start of the match a man dressed in the garb of the Ryūkyūan kings stands on a wooden platform hoisted in the air on the shoulders of men standing on opposite sides of the rope.
The "king" is carried on this platform down the length of the rope, before the festival starts, and the two kings perform a ritual sword contest.
The main rope, over one metre in diameter, has many smaller diameter, but very long ropes extending from it, and the participints pull these during the contest.
The contest lasts 30 minutes and the challenge is to pull the other team a total of 15 metres.
If neither side pulls the other the 15 metres, whichever side has pulled the other the furthest wins.
After the 30 minute time limit expires, one side is declared the victors, and they are allowed to climb on top of their rope to celebrate.
It is customary for participants to cut apart the rope, and take a length of it as a token, and so throngs of people using tools ranging from their pocket knives, scissors and hacksaws set on the rope cutting lengths of it to commemorate the festival.