Udema

An udema (Swedish pronunciation: [ˈɵdɛma] or [ˈudɛma]; also udenma) was a type of warship built for the Swedish archipelago fleet in the late 18th and early 19th centuries. It was developed for warfare in the Archipelago Sea in the Baltic and along the coasts of Svealand and Finland against the Russian navy. The udema was designed by the prolific naval architect Fredrik Henrik af Chapman for use in an area of mostly shallow waters and groups of islands and islets that extend from Stockholm all the way to the Gulf of Finland.

The udema was of an innovative new design with a single line of guns along the ship's centerline, a foreshadowing of the dreadnought battleships of the early 20th century. The design proved impractical for its time, however, and only three udemas were built between 1760 and 1776.

In the early 18th century, the establishment of Russian naval power in the Baltic challenged the interests of Sweden, one of the major powers in the Baltic. The Swedish empire at the time included territory in Northern Germany, all of modern Finland and most of the Baltic states, a dominion held together by the Baltic sea routes. Russian Tsar Peter the Great had established a new capital and naval base in Saint Petersburg in 1703. During the Great Northern War Sweden lost its Baltic state territories, and suffered from Russian raiding in Finland and along the chain of islands and archipelagos that stretched all the way from the Gulf of Finland to the capital of . The Swedes began building inshore flotillas of shallow-draft vessels, beginning with smaller versions of the traditional Mediterranean warships, the galleys. Most of these were more akin to galiots and were complemented with gun prams. The disastrous war with Russia(1741–43) and the minor involvement in Prussia in the Seven Years' War (1757–62) showed the need for further expansion and development of the inshore flotillas with more specialized vessels.

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