The Thirty Years’ War in Central Europe began when the Anglican Church was established in Germany and was met with resistance.
Lutheran princes challenged the Holy Roman Emperor, who was Catholic.
Lutheran princes battled Huguenot princes for control of German states.
Calvinists went to Germany to spread their beliefs and establish strict laws.

The Thirty Years' War was primarily fought in Central Europe between 1618 and 1648. Estimates of the total number of military and civilian deaths which resulted range from 4.5 to 8 million, the vast majority from disease or starvation. In some areas of Germany, it has been suggested up to 60% of the population died.[14]

Until 1938, the war was usually presented as a German conflict; this changed when historian CV Wedgwood argued it formed part of a wider, ongoing European struggle, with the Habsburg-Bourbon conflict at its centre.[15] This is now the generally accepted view, with related conflicts such as the 1568–1648 Eighty Years War, the 1635-59 Franco-Spanish War, and the 1629–31 War of the Mantuan Succession.[16]

Explanation:

from the religious point of view, the conflicts began because of the enmity between catholic and protestants. in 1649, at the insistence of baltimore, the colonial assembly approved the act of religious tolerance, the first law in the colonies granting freedom of worship, though only for christians. in 1654, however, with the protestants of maryland in the majority, the act was revoked. the almost civil war broke out and order was not restored until 1658, when lord baltimore was returned to power.

on the issue of class conflict, the chesapeake region offered few economic opportunities to contract employees who had served their term of obligation. even with the small amount of capital needed to grow tobacco, former hired servants at best became subsistence farmers, a mature class for those called to rebellion, such as those proposed by nathaniel bacon. as the number of new hired workers declined because of limited chances of progress and reports of severe treatment, they were replaced by african slaves.

from the racial point of view, after 1660, the chesapeake colonies imposed laws that defined slavery as a lifelong and hereditary condition based on race. this made slaves profitable because planters could rely not only on their work but also on their children. the slave population, which numbered four thousand in virginia and maryland in 1675, grew significantly by the end of the century.