The modernization of Russia continued during Catherine's reign. An increase in the number of books and periodicals also brought forth intellectual debates and social criticism of the Russian Enlightenment. In 1790, Aleksandr Nikolaevich Radishchev published his "Journey from St. Petersburg to Moscow", a fierce attack on serfdom and on the autocracy. Catherine, already frightened by the French Revolution, had Radishchev arrested and banished to Siberia. Radishchev later gained recognition as the father of Russian radicalism. In accordance with the treaty Russia had signed with the Georgians to protect them against any new invasion of their Persian suzerains and further political aspirations, Catherine waged a new war against Persia in 1796 after they had again invaded Georgia and established rule over it about a year prior and expelled the newly established Russian garrisons in the Caucasus.