GLASGOW — In this city defined by the rivalry between its two biggest soccer clubs — Celtic and Rangers — there were no team colors on display Sunday night as fans filtered into a gloomy pub to watch Scotland play Germany in its first qualifying game for the 2016 European Championship. There is, however, more than soccer to talk about at the moment.

Scotland is wound tight, waiting to uncoil next week, when the country will vote on whether it should be independent from Britain. The debate has generated the kind of tension and engagement usually reserved for soccer rivalries in Scotland, and in fact the country’s stadiums have become key battlegrounds for the yes and no campaigns.

And as is so often the case in Scotland, the rivals Rangers and Celtic, collectively known as the Old Firm, are dominating the outlook. To the surprise of no one, they seem to be, as with most things, on opposite sides.

Traditionally, Rangers is as British as afternoon tea or “Downton Abbey.” The club’s symbol is the Union Jack. It hosts an annual Armed Forces Day. It toasts the British monarch before its first home game each year. A portrait of Queen Elizabeth II even hangs in the dressing room at Ibrox Stadium.