Port Armstrong is an embayment on the southeast coast of Baranof Island, which extends west-southwest for 1.6 miles (2.6 km) from Point Eliza on Chatham Strait, and the site of a historical whaling station and present-day salmon hatchery, about 59 miles (95 km) south-southeast of Sitka and 4 miles (6.5 km) north of Port Alexander, Alaska. Port Armstrong was surveyed and named on a chart by Captain George Vancouver in 1794. The watershed draining into the bay is small with a stream that starts at an elevation of 1900 feet (580 m) and flows generally northeast for 1.6 miles (2.6 km) to Betty Lake at an elevation of 306 feet (93 m), which connects to Jetty Lake at an elevation of 270 feet (82 m), and then drains via a cascade of 0.4 miles (0.6 km) to the north shore of the bay. The southern tip of Baranof Island, and most of the Port Armstrong watershed is formed by the Baranof Accretionary Complex which is associated with the Chugach terrane and consists of sedimentary and volcanic rocks derived from oceanic crust that was subducting beneath an island arc. The sedimentary rocks at Port Armstrong developed during the Paleocene, or about 60 million years ago, and consists mostly of sandstone with grains of quartz, plagioclase, potassium feldspar, and biotite.

The southeast coast of Baranof Island is within the traditional territory of the Tlingit Kooyu Kwáan, or Kuiu Clan, historically associated with Tebenkof Bay on the west coast of Kuiu Island where 148 cultural sites were recorded on a recent archaeological survey. The sites were represented by house depressions, shell middens, cache pits, gardens, stone alignments, intertidal stakes, camps, and structures associated with fox farming. In 1799, the Russian-American Company established a trading post at Sitka called New Archangel to supply the maritime fur trade. In 1867, the Sitka post was transferred to the United States after the Alaska Purchase and within a few years miners, fishers, and traders began exploiting the largely unregulated resources. In 1878, the first cannery was established by the North Pacific Trading and Packing Company at Klawock on Prince of Wales Island. Within 10 years, the salmon fishery was forced to consolidate after the proliferation of canneries led to overexploitation of salmon, and out of 31 canneries in Southeast Alaska, only 9 remained by 1891. However, in 1929, there were 13 herring salteries and reduction plants operating in southern Chatham Strait, including one at Port Armstrong, that mostly impounded schools of herring with purse seines.

In 1910, Peter Bogen raised the funds to finance the U.S. Whaling Company, and purchased the Sommerstad for a floating processor, and had three catcher vessels named Star I, Star II, and Star III built at the Seattle Construction and Dry Dock Company. In 1912, whaling operations began at a shore station established at Port Armstrong and within 6 weeks, 71 whales were caught. In the first year, the ships caught 314 whales and produced 8,500 barrels of oil, which was only a quarter of what had been estimated. In 1913, the total catch was 75 sperm whales, but the oil yield was below expectations. The company processed the whales into oil, fertilizer, and bone meal. Starting in 1914, the three whalers wintered at Eagle Harbor near Seattle and returned to Port Armstrong in the spring. In 1916, the shore station needed to be rebuilt after it was partly destroyed by winter storms. In 1917, the whaler Star I was ordered delivered to the Navy for service as a minesweeper in the Pacific Northwest during World War I. The vessel was returned to the U.S. Whaling Company in 1919, and all three whalers were back at work, but low whale stocks, high operating costs, and an end to the high wartime demand made the venture marginally profitable. In 1922, the company took 117 whales, including 60 sperm whales, and this was the last year the company reported. In 1925, the Buchan & Heinen Company leased the whaling station at Port Armstrong and bought a new herring reduction unit from the California Press Manufacturing Company to produce herring oil and fish meal.  The herring reduction plant operated until 1958. Today, Port Armstrong is the site of the Armstrong-Keta salmon hatchery. See a short video about shore whaling in the early 1900s here. Read more here and here. Explore more of Port Armstrong and Baranof Island here: