Berlin (CNN) Every public building in the southern German state of Bavaria is now required to display a Christian cross at the entrance to greet visitors.

The law, which came into effect Friday, has re-ignited a fierce national debate about the role of religion in politics and what it means to be German.

"The cross is a fundamental symbol of our Bavarian identity and way of life. It stands for elementary values such as charity, human dignity and tolerance," declared Bavarian State Premier Markus Soder at a cabinet meeting in April when the new requirement was announced. He then walked out and nailed a cross to the wall of the lobby in the Bavarian State Chancellery.

Parts of Germany have been grappling with a crisis of identity after the country accepted more than a million refugees in 2015, many of whom are Muslims.

Many arrived across the border from Austria, entering Germany via Bavaria, one of Germany's most politically and socially conservative states. It also has one of the highest proportions of Christians -- in the 2011 census , over 75% of Bavarians identified as Roman Catholic or Protestant, compared to 62% nationwide.

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