The Mather-Walls House in Keewatin (now part of Kenora) reflects the vision of one man – John Mather.

Mather, a native of Scotland who emigrated to Canada in 1857, became Keewatin's first postmaster and school board chairman. A shrewd businessman, he acquired the lumber rights to an area around Lake of the Woods at a time when railway construction dominated the local economy. Mather formed the Keewatin Lumbering and Manufacturing Company and hired workers from as far away as Scotland.

In 1889, Mather built three almost identical houses for his employees. The first and third have undergone significant alterations over the years. The second, originally the residence of Mather's son David, is now known as the Mather-Walls House.

Preserved by the Ontario Heritage Trust, the Mather-Walls House is a conservative wooden version of the exuberant Queen Anne style, designed by Winnipeg architect George Browne. It has a picturesque roof line, verandas, fine interior wood trim and hardware, and windows in a variety of shapes and forms decorated with panes of coloured glass. In 1906, the house was purchased by John Walls, foreman at the mill. Located on a hill, it originally overlooked the lumber and flour mills across the bay. Today, it is home to the Lake of the Woods Historical Society. The house features furnishings from the era of the Walls family, as well as an interpretive display highlighting the Mather family's significant impact on the development of the area.

The Trust purchased the Mather-Walls House in 1975. Between 1975 and 1984, it conducted extensive research, then undertook a complete restoration of the site.

The Lake of the Woods Historical Society has operated the Mather-Walls House, since it opened in 1985, under an agreement with the Trust. The Society holds its meetings and hosts community events on the premises, and in the summer months conducts public tours (now closed for the season).