In what year was the team founded that won the 1956-1957 Irish League championship?
Glenavon F.C. Glenavon Football Club is a semi-professional, Northern Irish football club playing in the NIFL Premiership. The club, founded in 1889, hails from Lurgan and plays its home matches at Mourneview Park. Club colours are blue and white. Gary Hamilton has been player-manager of the Lurgan Blues since December 2011 following the resignation of Marty Quinn.
League of Ireland First Division The League of Ireland First Division (Irish: "Céad Roinn Sraith na hÉireann" ), also known as the SSE Airtricity League First Division, is the second level division in both the League of Ireland and the Republic of Ireland football league system. The division was formed in 1985. It replaced the League of Ireland B Division as the League of Ireland's second level division. Since 2003 the First Division has operated as a summer league.