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The Embargo Act of 1807, adopted during the Napoleonic Wars, and the War of 1812 significantly curtailed Boston's harbor activity. Although foreign trade returned after these hostilities, Boston's merchants had found alternatives for their capital investments in the interim. Manufacturing became an important component of the city's economy, and by the mid-19th century, the city's industrial manufacturing overtook international trade in economic importance. Until the early 20th century, Boston remained one of the nation's largest manufacturing centers and was notable for its garment production and leather-goods industries. A network of small rivers bordering the city and connecting it to the surrounding region facilitated shipment of goods and led to a proliferation of mills and factories. Later, a dense network of railroads furthered the region's industry and commerce.

What became an important part of the city's economy during the Napoleonic Wars and the war of 1812?
manufacturing