Paul I of Russia
Paul I (; "Pavel Petrovich") ( – ) reigned as Emperor of Russia between 1796 and 1801. Officially, he was the only son of Peter III and Catherine the Great, though Catherine hinted that he was fathered by her lover Sergei Saltykov, who also had Romanov blood, being a descendant of the first Romanov tsar's sister, Tatiana Feodorovna Romanova.
Alexander I of Russia
Alexander I (, Aleksandr Pavlovich; – ) reigned as Emperor of Russia between 1801 and 1825. He was the oldest son of Paul I and Sophie Dorothea of Württemberg. Alexander was the first Russian King of partitioned Poland, reigning from 1815 to 1825, as well as the first Russian Grand Duke of Finland, reigning from 1809 to 1825.