Frederick Chalmers, son of Robert Hamilton Chalmers and Emily Lousia (Walter) Chalmers, was born in Brighton, Tasmania on 4 January 1881, into a farming family. He had four brothers and four sisters. At age 18 he enlisted in the army and served in South Africa during the Boer War, obtaining the rank of Lieutenant in 1901. After demobilization he returned to Tasmania, where he lived until 1907. He then joined the railway company of the State of Victoria, and worked as a salesman at Moe. Married to Mary Cecilia Bennett in 1910, he became a widower in 1914, and in April of the same year he re-enlisted in the Army. Joining the Australian Imperial Force as an enlisted man, he was promoted to lieutenant a month later. During the First World War he served in Egypt, Gallipoli, Belgium, and France.