Potemkin's Black Sea Fleet was a massive undertaking for its time. By 1787, the British ambassador reported twenty-seven ships of the line. It put Russia on a naval footing with Spain, though far behind the Royal Navy. The period represented the peak of Russia's naval power relative to other European states. Potemkin also rewarded hundreds of thousands of settlers who moved into his territories. It is estimated that by 1782 the populations of Novorossiya and Azov had doubled during a period of "exceptionally rapid" development. Immigrants included Russians, foreigners, Cossacks and controversially Jews. Though the immigrants were not always happy in their new surroundings, on at least one occasion Potemkin intervened directly to ensure families received the cattle to which they were entitled. Outside of Novorossiya he drew up the Azov-Mozdok defense line, constructing forts at Georgievsk, Stavropol and elsewhere and ensured that the whole of the line was settled.