Timberjack was founded in Woodstock, Ontario in the 1950s by Wesley Maggill and Robert Simons, who designed an articulated
four-wheel drive tractor with a winch at the back. They produced a prototype and production took off from there. There were affiliations with King Trailer ind. and with Timberland Ellicott Corp. before Eaton Corporation purchased Timberjack and named it the Forestry Equipment Division.The traditional color of all Timberjack products was a reddish orange. The later green colored machines were made by John Deere.
Timberjack was owned by the Eaton Corporation in the 1960s, 1970s and early 1980s. In 1984 Timberjack management made a leveraged buyout from Eaton to become an independant company. Then Timberjack was acquired by FMG (ForestMachineGroup), owned by Finnish Rauma-Repola. After a short period carrying the double-name FMG-Timberjack, in 1993 Timberjack became the brandname for the group. Other well known forest machine brands, which have been incorporated into FMG-Timberjack were Swedish Kockums,ÖSA and Bruun system as well as Finnish LOKOMO.
In December 2000 John Deere bought Timberjack from Metso Corporation which was formerly known as Rauma-Repola for $570 million dollars which also included the purchase of a separate company, Waratah, a leading manufacturer of heavy-duty harvester heads.
As of June, 2005, at the forestry fair "ELMIA Wood", the Timberjack product line was discontinued, and John Deere, its parent company, became the largest single brand of forestry equipment. Its global market share for both Cut-to-length and Full tree equipment is estimated to 45%.