Final answer:
Louis Philippe I was the Citizen King who reigned from 1830-1848 before being replaced by Napoleon III.
Step-by-step explanation:
The citizen king in the 1830-1900s was Louis Philippe I. He reigned from 1830 to 1848. Louis Philippe I was the King of the French and was known as the 'Citizen King' because he presented himself as a constitutional monarch who was in touch with the interests of the people. He was the last king of the French before the establishment of the French Second Republic in 1848.
After Louis Philippe I, he was replaced by Napoleon III, who established the French Second Empire and reigned as Emperor from 1852 to 1870.
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