A total of 78 fixtures have taken place between the two, with the Nottingham outfit holding the upper hand historically, as 31 games have been won by the Magpies, with 28 O's wins and 19 draws.
Leyton Orient were founded in 1881, and have had several name changes throughout the years, including Eagle Cricket Club, Orient FC and Clapton Orient FC. The O's, who play in Waltham Forest, are the second-oldest league club in London behind Fulham.
The club's unusual name is alleged to come from one of the club's early players (Jack R Dearing) who was an employee of the Orient Shipping Company.
During the First World War. 41 members of the Clapton Orient team and staff joined up into the 17th Battalion Middlesex Regiment (the Footballers' Battalion), the highest of any football team in the country and the first to join up en masse.
During the Battle of the Somme, three players gave their lives for King and Country: Richard McFadden, George Scott and William Jonas. Prior to the First World War, O's striker Richard McFadden had saved the life of a boy who was drowning in the River Lea as well as rescuing a man from a burning building.
History was made on Saturday 30th April 1921 when the Prince of Wales, later to become King Edward VIII, visited Millfields Road to see the O's play Notts County. The Orient won 3-0 and this was the first time a member of royalty had attended a Football League match.
Leyton Orient were involved in a dispute with the Premier League over its decision to allow West Ham to use the Olympic Stadium in London, with the O's expressing an interest in the 2012 Olympics venue, but this has now been settled with a "confidential agreement".
Arguably the most famous fans of the club are Andrew and Julian Lloyd Webber. The album Variations, used as the theme tune for London Weekend Television's South Bank Show, was written by Andrew as the result of his losing a bet to his brother on the result of a Leyton Orient match. Julian later presented a gold disc of Variations to the club chairman at half time during a game with Leicester City.
In addition, David Beckham and Alfred Hitchcock were born in the borough.
Team news
Leyton Orient will be without defender Nicky Hunt against Notts County after he was booked for the 10th time this season in the dramatic win at Plymouth in midweek.
Hunt serves a two-game ban as the O's look to stretch their unbeaten run to three games.
Manager Danny Webb is also waiting to see if midfielder Liam Kelly will be available after he was charged with violent conduct by the Football Association for pushing a ball boy at Home Park.
Elsewhere, defender Yvan Erichot and midfielder Nigel Atangana are doubts after missing Tuesday's game with groin injuries.
Striker Paul McCallum is set to miss out as he struggles with a recurring knee problem while Sammy Moore is a doubt through illness.
Thierry Audel is an injury concern for Notts as he is nursing a thigh problem following the midweek draw with Exeter and will be assessed before the Magpies travel.
Haydn Hollis has been overlooked by Notts boss Kevin Nolan for the last two matches but the defender will hope to come back into the squad, especially if Audel is absent.
Nolan, on his first return to the club who gave him his first management job, also has the likes of Shola Ameobi, Jonathan Forte and Jorge Grant pushing for starting places.
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