In association football, a League Cup or Secondary Cup generally signifies a cup competition for which entry is restricted only to teams in a particular league. The first national association football tournament to be called "League Cup" was held in Scotland in 1946/47 and was entitled the Scottish League Cup. However, in the Republic of Ireland the now defunct League of Ireland Shield was the first national league-only tournament of its kind; this was subsequently replaced by the League of Ireland Cup in 1973.
The creation of a League Cup marked the difference from the Association Cup or Primary Cup, which is generally also open to teams from multiple leagues, often as far down as regional amateur leagues, and who are also memebers of the country's football association.
The creation of a tournament of this kind exclusively for the top national-level league teams, in addition to the two main domestic association football tournaments of the league and association cup, also created a new national footballing achievement called the domestic "treble"; see Treble (association football). The first national league treble of this kind was won by Shamrock Rovers of the Republic of Ireland in 1925.
League cups were generally introduced after the Second World War - for example, the Football League Cup in England in 1960 - although in other countries they were created following a rise in the number of floodlit stadiums, allowing regular midweek matches.
In certain countries, the League Cup had, or in some cases still has, group stages in the early stages. These often opened the season before the main league season began.
List of League Cups and Secondary Cups
Football League Cup (England)
Finnish League Cup (Finland)
Coupe de la Ligue (France)
Hong Kong League Cup (Hong Kong)
Ligakupa (Hungary)
Deildabikar (Iceland)
Toto Cup (Israel)
K-League Cup (South Korea)
J. League Cup (Japan)
Irish Football League Cup (Northern Ireland)
Taça da Liga (Portugal)
League of Ireland Cup (Republic of Ireland)
Scottish League Cup (Scotland)
Singapore League Cup (Singapore)
Telkom Knockout (South Africa)
Trinidad and Tobago League Cup (Trinidad and Tobago)
Welsh League Cup (Wales)
Defunct
Belgian League Cup (Belgium, defunct)
Bulgarian Cup then Cup of the Soviet Army (Bulgaria, defunct)
Spar Cup, Danish League Cup and Viasat Cup (Denmark, defunct)
Coupe Charles Drago (France, defunct)
DFB-Ligapokal (Germany, defunct)
Greek League Cup (Greece, defunct)
Norwegian League Cup (Norway, defunct)
Ekstraklasa Cup (Poland, defunct)
Cupa Ligii (Romania, defunct)
Russian Premier League Cup (Russia, defunct)
Saint Mungo Cup and Scottish Summer Cup (Scotland, defunct)
Copa de la Liga (Spain, defunct)
Swiss League Cup (Switzerland, defunct)
Tunisia Coupe de la Ligue Professionel (Tunisia, defunct)
USSR Federation Cup (USSR, defunct)
FAW Premier Cup (Wales)
For Women
Premier League Cup (England)
Scottish Premier League Cup (Scotland)
(source:wikipedia)
