Classical Athens, for example, forced weaker states into the Delian League and in some cases imposed democratic governments on them.
[citation needed] The number of tributary or vassal states varied over time but most notable were the Khanate of Crimea, Wallachia, Moldavia, Transylvania, the Sharifate of Mecca, and the Sultanate of Aceh.
[citation needed] Austria-Hungary tried to make Serbia a client state in order to form a Christian opposition to the Ottoman Empire, but after the 1903 May Coup, Serbia came under the influence of Russia, which was forming a pan-Eastern Orthodox opposition to the Latin Christianity represented by the Austro-Hungarian Empire.
[10] During the Revolutionary and Napoleonic eras (1789–1815), France conquered most of western Europe and established several client states.
But in both cases, the economic and military reality did not amount to full independence, but a status where the local rulers were British clients.
Other instances include Africa (e.g. Northern Nigeria under Lord Lugard), and the Unfederated Malay States; the policy of indirect rule.
[17][18][19] In the late 19th century, the Empire of Japan gradually reduced Joseon Korea's status to that of a client state.