Page "Kingdom of Prussia" Paragraph 22

As to religion, reformed Calvinist Frederick William III — as Supreme Governor of the Protestant Churches — asserted his long-cherished project ( started in 1798 ) to unite the Lutheran and the Reformed Church in 1817, ( see Prussian Union ).

The Calvinist minority, strongly supported by its co-religionist Frederick William III, and the partially reluctant Lutheran majority formed the united Protestant Evangelical Church in Prussia.

However, ensuing quarrels causing a permanent schism among the Lutherans into united and Old Lutherans by 1830.