Already on 10 March 1788 Crown was promoted to Captain-Lieutenant and appointed commander of the 22-gun cutter Merkuriy, which was part of the Baltic fleet squadron Copenhagen.

On this ship, Captain Crown carried out patrol services during the Russian-Swedish war in the Baltic Sea.

In recognition of his merits, he was awarded the Order of Saint Vladimir 3rd class and promoted to 1st rank captain (Captain-Commodore).

In 1791 Crown, together with many other naval officers of British origin, was transferred to the Black Sea in expectation of war with England.

In 1814 he was blockading the Dutch coast together with an English squadron, and after the Bourbon Restoration, he transported King Louis XVIII from London to France on board his flagship.