Frederick William was determined to unify the Protestant churches, to homogenize their liturgy, their organization and even their architecture.
The long-term goal was to have fully centralized royal control of all the Protestant churches in the Prussian Union of churches.
 The merging of the Lutheran and Calvinist (Reformed) confessions to form the United Church of Prussia was highly controversial.
Angry responses included  a large and well-organized opposition.
Especially the "Old Lutherans" in Silesia refused to abandon their liturgical traditions.
The crown responded by attempting to silence  protest.
 The stubborn Lutheran minority was  coerced by military force, the confiscation of their churches and the imprisonment or exile of their pastors.
By 1834 outward union was secured on the basis of common worship but separate symbols.
The opponents of the measure being forbidden to form communities of their own.
Many left Prussia.
The King's unsuccessful counterattack worsened  tensions at the highest levels of government.
The crown's aggressive efforts to restructure religion were  unprecedented in Prussian history.
 In a series of proclamations over several years the Church of the Prussian Union was formed, bringing together the majority group of Lutherans, and the minority group of Reformed Protestants.
The main effect was that the government of Prussia had full control over church affairs, with the king himself recognized as the leading bishop.

In 1824 Frederick William III remarried (morganatically) Countess Auguste von Harrach, Princess of Liegnitz.
They had no children.

In 1838 the king distributed large parts of his farmland at Erdmannsdorf Estate to 422 Protestant refugees from the Austrian Zillertal, who built Tyrolean style farmhouses in the Silesian village.
Frederick William was determined to unify the Protestant churches, to homogenize their liturgy, their organization and even their architecture. The long-term goal was to have fully centralized royal control of all the Protestant churches in the Prussian Union of churches.  The merging of the Lutheran and Calvinist (Reformed) confessions to form the United Church of Prussia was highly controversial. Angry responses included  a large and well-organized opposition. Especially the "Old Lutherans" in Silesia refused to abandon their liturgical traditions. The crown responded by attempting to silence  protest.  The stubborn Lutheran minority was  coerced by military force, the confiscation of their churches and the imprisonment or exile of their pastors. By 1834 outward union was secured on the basis of common worship but separate symbols. The opponents of the measure being forbidden to form communities of their own. Many left Prussia. The King's unsuccessful counterattack worsened  tensions at the highest levels of government. The crown's aggressive efforts to restructure religion were  unprecedented in Prussian history.  In a series of proclamations over several years the Church of the Prussian Union was formed, bringing together the majority group of Lutherans, and the minority group of Reformed Protestants. The main effect was that the government of Prussia had full control over church affairs, with the king himself recognized as the leading bishop.
In 1824 Frederick William III remarried (morganatically) Countess Auguste von Harrach, Princess of Liegnitz. They had no children.
In 1838 the king distributed large parts of his farmland at Erdmannsdorf Estate to 422 Protestant refugees from the Austrian Zillertal, who built Tyrolean style farmhouses in the Silesian village.
Frederick William III of Prussia