What were some of the most well known leaders of the world in the Baroque era ? (1600-1750)

Many to choose from. Here are
three:

Louis XIV reigned in France from 1643-1715, 72
years, during which he rose France to one of the largest European powers, centralizing
the government more on economic, trade and colonization, giving more power to the Crown
than to the aristocracy or the Church.  This was a move to a more modern
State.

Peter I (Peter the Great) reigned from 1682 until
1725. He modernized Russia dramatically and quickly (by studying in Europe, which at the
time was considered treasonous) and changed the country into a major international power
by implementing progressive government reforms.

Charles I
ruled England from 1625-1649. His reign ended with his execution, the English Civil War.
In the aftermath, Oliver Cromwell would lead England in a short lived republican state.
Charles’ impositions with taxation and his overriding Parliament led to the English
Civil War, which led to the 10 years England would exist as a Commonwealth. Although the
monarchy was restored in 1660, this series of events were major in the gradual
transformation from absolute to constitutional monarchy.