The Celtic F.C. is a soccer team.
The Celtic Football Club ( [ ˈsɛltɪk ] ) is a professional football club based in Glasgow , Scotland , which plays in the Scottish Premiership . The club 's greatest season was 1966 -- 67 , when Celtic became the first British team to win the European Cup , also winning the Scottish league championship , the Scottish Cup , the League Cup , and the Glasgow Cup .