The municipality of Waltham was named after a village near Grimsby in England. Incorporated as a municipality in 1859, Waltham's first mayor was John T. Coghlan. By 1859, the Township of Bryson, named after George Bryson, amalgamated with Waltham. The town of Waltham was the terminus of the PPJ railway line and later the Canadian Pacific railway. Built in 1887, the railway offered a direct means of travel between the Upper Pontiac and Ottawa. The train would arrive in Waltham in the evening, and leave the next morning for Ottawa. The railway was vital for the region. Besides creating jobs, the railway provided passenger transport as well as carrying mail and freight. The Canadian Pacific Company ended its service to the Pontiac in 1959 but the region's people retain fond memories of the railway. Now the rails are gone and the MRC has obtained a right of way on the old line for recreational travel. A trail called the PPJ Cyclopark goes from Waltham to Bristol and is perfect for bicycle and snowmobile enthusiasts.
The Waltham hydroelectric station is situated at the mouth of the Black River. It now belongs to the Pontiac Hydro Commission but once was part of the Pembroke Electric Light Company network. This hydroelectric station dates from the beginning of the 20th century and is reputed to be the first commercial station in Canada. Even today one of the machines built in 1918 is still used to supply power to neighbouring villages as well as the town of Pembroke.
North of Waltham, there is a vast extended tract of undeveloped land. Originally leased by the timber baron J.E. Booth and the McLaughlin Company, it is now leased by Smurfit Stone as a lumbering area. This region is a true paradise for hunting and fishing.