In September and November of 1836 the Surveyor General Captain John Septimus Roe led a 40-day expedition out into the unknown east of the settled districts of the Avon Valley. Mt Marshall and Lake McDermott were named after Captain Marshall McDermott, an early settler to the Swan River Colony. Sandalwooders and Graziers were the first European settlers in the Mt Marshall area. The first grazing lease was taken up in 1868. Sandalwood was removed from this area from the 1880's through to the 1920's. Permanent settlement and development of the land for farms commenced around 1910. Prior to 1923 this area was part of the Ninghan Road District. In June 1923 the Mt. Marshall Road District was gazetted. At this time the district was divided into six Wards and an election was held in August of that year.
The Shire of Mt Marshall covers an area of 10 134 square kilometres and is situated in the North Eastern Wheatbelt region. The Shire is approximately 273 kilometres northeast of Perth and has borders with the Shires of Trayning, Koorda, Mukinbudin, Yalgoo, Dalwallinu, Westonia, Yilgarn, Wyalkatchem, Sandstone and Menzies. The area is primarily wheat, coarse grain, cattle and sheep farming district. There are many points of interest all serviced by the two main centres, Bencubbin and Beacon. At the first meeting, held in August 1923, Mr. L.K. Hammond was elected Chairman and Mr. L.R. Latham was appointed as the first Secretary. Mr. Hammond went on to serve the district for thirty-three years. Rates were set at a penny ha'penny in the pound on land valuations. Land was divided into three classes with first class land being valued at fifteen shillings an acre, second class land was valued at ten shillings an acre and third class land at eight pence per acre.
By 1929 the Waddouring Rock catchment dam opened and water was available for the townsites of Bencubbin and Gabbin. In this year the Road Board raised a loan for an electricity supply for Bencubbin. The estimated population of the district at that time was two thousand two hundred people. Development extended to the northern area of the Shire and in 1930 the railway was extended from Burakin to Bonnie Rock. Beacon and Wialki Primary Schools opened in 1932. The depression and a series of drought years during the thirties resulted in over a hundred farms being forfeited to the Crown. By 1940 the population had dropped by fifty percent to one thousand two hundred and sixty in the space of ten years. In this same time frame sheep numbers had increased three hundred percent and the area covered by the Road District had increased from one thousand six hundred and seventy three square miles to four thousand two hundred and thirty two square miles. The war years resulted in very slow growth in the district due to a shortage of labour. and the rationing of fuel, tyres and other necessary commodities. Council's revenue doubled between 1940 and 1949 and the population dropped to seven hundred and fifty. Sheep production meanwhile had doubled. By this time there were one hundred and thirty seven holdings in the district. During the 1950's more farms were developed and the population increased to one thousand by 1959. The sheep and grain production increased and there was a decrease in the stigma of the 'marginal' label. The Mt. Marshall Road Board conducted the first naturalisation ceremony on 17th November 1955. The candidates were Bencubbin residents Joseph Skender and Michael Tomkowick.
The Road Board became the Mt. Marshall Shire Council in 1960 and in the next decade there was considerable expansion in the district. It was in this decade that the district expanded to have Machinery Dealers, 'A' class fuel depots, new shops, housing and sale yards. It was also in this decade that both Bencubbin and Beacon built Silver Chain Centres. It was in this decade that the Bencubbin power supply was taken over by the State and Beacon was connected to the Comprehensive Water Scheme while Council took over the provision of power to the Beacon town-site. Wheat quotas and the drought of 1969 saw a drop in the population of approximately two hundred and fifty as farms and businesses had to let staff go.
By 1979 the population was estimated at one thousand and there were three hundred and twenty ratepayers. There was electricity to all town-sites and approximately ninety percent of farms. The Comprehensive Water Scheme serviced the towns of Beacon, Bencubbin, Gabbin and Welbungin. In addition about forty-five percent of farms also had access to the scheme. There were one thousand two hundred and twenty km of road with two hundred and forty km sealed. Spiralling interest rates during the 1980's brought about a decline in the farms and businesses in the district. The Rural Counselling Service (RCS) was established and managed by a committee, overseen by the Shire which contributed funds and in kind support to the service. The RCS was to assist farming families to negotiate with their bankers, develop manageable business plans and if necessary transition out of farming. When the farming community is under financial pressure there is always a flow on to the other services in town, and in this time frame there was a decline in the population.
The technological explosion of the last twenty years has enabled remote delivery of services and information, which results in the withdrawal of 'shop fronts' and staff from the district and has a snowball effect on the whole community. Currently the population of the Shire of Mt Marshall is approximately 615 people. The Shire currently employees just under 30 staff members to cover the areas of roads, rates, rubbish, town maintenance, gardens and recreation facilities, finance, community development, housing, emergency services and more.