The USRC Mackinac, later known as USCGC Mackinac, was a patrol vessel constructed by the Spedden Company in Baltimore, Maryland, and launched on October 11, 1902. She was commissioned into the United States Revenue Cutter Service on October 29, 1903, becoming the first vessel to bear the name. The ship was primarily designed for patrol and customs enforcement duties on the Great Lakes, with an initial assignment to Erie, Pennsylvania. Mackinac was a relatively small vessel optimized for regional patrol duties, and her operational pattern was seasonal, reflecting the harsh winter conditions of the Great Lakes. Each year during the navigation season, she operated on the lakes, including duties such as boarding vessels, enforcing regulations, and customs work. In the spring of 1905, she briefly served along the Massachusetts coast before being reassigned to Sault Ste. Marie, Michigan, on April 25, 1905, to focus on customs enforcement and vessel regulation in the St. Mary's River. During winter months, when the lakes froze, she was laid up at Milwaukee, Wisconsin. Following the establishment of the Coast Guard in 1915 through the merger of the Revenue Cutter Service and the Lifesaving Service, Mackinac was redesignated USCGC Mackinac. Her routine operations continued until 1917, when she was requisitioned by the U.S. Navy for wartime service during World War I. As USS Mackinac, she served in the Atlantic, patrolling the 3rd Naval District along the U.S. East Coast. After the war, she was returned to the Coast Guard on September 22, 1919, and stationed in Boston, Massachusetts, where she continued patrol duties along the New England coast. Mackinac remained in service until her decommissioning on June 8, 1939, marking a lengthy career characterized by regional patrol, enforcement, and wartime service, highlighting her role in maritime security on the Great Lakes and Atlantic coasts over more than three decades.

This description has been generated using GPT-4.1-NANO based on the Vessel's wikidata information and then modified by ShipIndex.org staff.