Of all the struggles that took place along the border between the United States and the British provinces in Canada during the War of 1812, the one that lasted the longest was the battle for control of Lake Ontario. Because the armies depended on it for transportation and supply, control of the lake was a key element in American invasion attempts and the defensive actions of the British. In the end, unprecedented freshwater fleets had been built in Kingston and Sackets Harbour, domination had passed back and forth, but the contest had not been won decisively by either side. Lords of the Lake is the first full-length study of this aspect of the War of 1812. It tells the story of how the contest was waged from the days of the incompetent Provincial Marine squadron to the launch of the 104-gun ship St. Lawrence. The feats and failures of the opposing commodores, Isaac Chauncey and Sir James Yeo, are described, as are the roles played by key military and political leaders in shaping the course of the war.