Final answer:
Mikhail Speransky was a liberal advisor to Tsar Alexander I and was later sent to Siberia as governor-general due to his reformist views.
Step-by-step explanation:
Speransky, known more formally as Mikhail Speransky, was a Russian statesman during the reign of Tsar Alexander I. He is best known for his role as a liberal advisor to the Tsar. Although he initially had conservative leanings, his ideologies evolved, and he eventually became a proponent of liberal reforms in the Russian empire. Speransky was tasked with drafting the first Russian constitution and later became the governor-general of Siberia. His appointment to Siberia was a form of political exile due to his progressive views, which were seen as a threat to the conservative establishment.