The Lake of the Woods Milling Company Limited was started May 21, 1887 to take advantage of the new railway and western grain production.
Formed by a team from the board of Canadian Pacific Railway, including George Stephen, 1st Baron Mount Stephen, William Cornelius Van Horne and James Ross, the headquarters were in Montreal, while the milling operations were based in Keewatin, Ontario. The location provided transportation via the CPR, access to raw product, and water-power from the Winnipeg River.
The first mill was completed in 1888 with vice-president John Mather overseeing construction. It had a capacity of 140,000 bushels and a daily production capacity of 800 barrels of flour. The flour was marketed under the name Five Roses, which became a world famous brand. In 1913, Lake of the Woods released the first edition of the Five Roses Cook Book, which is still in production to this day.
The mill operated in Keewatin for 79 years, closing in 1967. At the height of its production, it was possibly the largest flour mill in the British Commonwealth.