The Seward Peninsula is a large peninsula on the western coast of the U.S. state of Alaska. It projects about 320 kilometers (200 mi) into the Bering Sea between Norton Sound, the Bering Strait, the Chukchi Sea, and Kotzebue Sound, just below the Arctic Circle. The entire peninsula is about 330 kilometers (210 mi) long and 145 km (90 mi)-225 km (140 mi) wide. Like Seward, Alaska, it was named after William H. Seward, the United States Secretary of State who fought for the U.S. purchase of Alaska.
The Seward Peninsula is a remnant of the Bering land bridge, a roughly thousand mile wide swath of land connecting Siberia with mainland Alaska during the . This land bridge aided in the migration of humans, as well as plant and animal species from Asia to North America. Archeological discoveries throughout the Chukotka Peninsula and Seward Peninsula show proof that Inupiat people have been living in the region for thousands of years. Excavations at sites such as the Trail Creek Caves and Cape Espenberg in the Bering Land Bridge National Preserve as well as Cape Denbigh to the south have provided insight into the timeline of prehistorical migrations from Asia to the Seward Peninsula.
Most of the peninsula is in the Nome Census Area, but part is in the Northwest Arctic Borough. These are the communities on the Seward Peninsula, with 2005 state population estimates: