Frederick the Great
He was influenced by Voltaire thanks to his enthusiastic verse dedications, contrasting him with the French monarch, the frivolous Louis XV.
Catherine the Great
The queen was concerned about attracting architects, philosophers, scientists, and artists to her court, which led to the acquisition of Diderot's complete library and was assiduously allied with D'Alembert and Voltaire who were in charge of illustrating it.
Joseph II
1741, ruled 1780-1790, Austria, abolished serfdom and imposed a single tax for all and also a physiocratic idea
Peter the Great
Patrick Gordon, François Lefort, and with the Dutch Andrés Vinicius, they influenced him by making him aware of Western modernities, later they would be his main advisers on political and military issues.
Maria Theresa
He made a series of reforms to support the country, beginning with a national army, limiting power to the Catholic Church, making the lords of that time have less power over the people.