In the early 1900's homesteaders arrived in the area. The first settlement was named in 1914 after Dr. John.K. McLennan who was involved with the Edmonton, Dunvegan, and British Columbia Railway. In January of 1915 the railway finally reached McLeann and and the first train station was built. McLennan was originally established as the major railway centre in northwestern Alberta.The first post office also opened in 1915 with E.E. Appleton the first postmaster. In 1918 the first residential lot was sold to Percy Jones and built the first house of McLennan. The first Hospital was opened in Dec of 1929 and was called the Sacred Heart Hospital that had 21 patient beds and later in 1952 it was expanded to include 37 beds. A new hospital was built in 1955 with a 62-bed capacity and many modern facilities. McLennan's strategic location along the railway and Highway 2 made the community important during the construction of the Alaska Highway in 1942. Over the years the community grew. It became a village in 1944 and shortly after in 1948 McLennan was incorporated as a town.