Adam Smith Cattanach was not named after the great economic thinker, but after his mother, Sarah Cattanach, nee Smith. He was the son of Henry James Goodriche Cattanach (b.18/9/1833), a land agent, who had migrated to Australia from Scotland. Adam Cattanach was the seventh child, following on from Christina (b.1864). Sarah (b.1865), Jane (b.1867), Harriet (b.1871), Harry (b.1875), Adam (b.1877), Anne (b.1879), and Maud (b.1882). 

His brother, Harry, had enlisted in the 5th Victorian Mounted Rifles in February, 1901, to fight in the 2nd Boer War. It was to be a twelve month engagement, with preference given to those who had returned from South Africa, with single men preferred and rejection for any man who weighed more than 12 stone. Harry Cattanach was single and presumably, within the weight limit. At that stage, he was working as a labourer in Jeparit, Wannon, Victoria. 

When Adam Cattanach enlisted in 1915, his father was dead (1911), and the family had moved from its previous address at 55 Gipps St. to 115 George St., both in East Melbourne. Adam Cattanach enlisted at Seymour, Victoria. He was working in the country as a sheep station overseer, was nearly 39 years old and a single man. He was taken on strength with the 10th Training Battalion, then embarked on HMAT Ascanius on 27 May, 1916, to England. On 9 December, he was taken ill with laryngitis, but was released from hospital on 21 December and sent to the Australian Division Base Depot before being transferred to France at Etaples. Here he was moved from the 5th Battalion to the 59th Battalion.  

The 59th Battalion had suffered heavy losses  at Fromelles in July 1916. From there, they had beeen rotated in and out of the front line over the 1916-17 winter. Adam Cattanach joined them on 3 November, 1916, and would have been taken part in the German retreat to the Hindenburg Line in March. The 59th were not involved in the assault on the Hindenburg Line, but fought in the 2nd Battle of Bullecourt, then in September, 1917, at Polygon Wood, March 1918 at Corbie and at Villers-Brettoneux in April. In September, they fought at Peronne, where the Allied forces broke through at St. Quentin Canal. In early October, they were resting behind the lines and were not at the front when the war ended on 11 November, 1918. Other than one brief period of furlough from 28 December 1917 to 11 January, 1918, Adam Cattanach was with the 53rd during all this period.

He returned to Australia on board the SS Port Lyttleton, leaving England on 10 June, 1919, and arriving in Melbourne on 5 August. He was discharged from further service on 19 September, 1919. In 1922, he was working on a property at Glenthompson, 'Loval Dale' owned by R.A. Fraser. This was probably near where he had been working at the time he enlisted and he was to stay there until at least 1949, when his electoral record ends. He died in 1950 at Willaura, Victoria, aged 73, and is buried in the Glenthomspon Cemetery. His name is listed on the Broadford Presbyterian Roll of Honour, the Broadford Roll of Honour and the RSL Virutal Memorial..