Lewis William Cozens was born in Newcastle NSW  on 24 September, 1885, the eldest son of Evan William Richard Cozens and his wife, Mary, nee Jeffrey. He was to have three sisters, Eleanor jane, b. 1883, Emily May, b. 1884, and Marion Irene, b. 1885. He may also have a brother, either Alan or Jeffrey Gully Cozens. In 1946, Lewis Cozens was living at 471 Featherstone St., Palmerston North, New Zealand, with Alan, Jeffrey, Florence Cozens, a married woman, and May Irene, presumably the Marion of the birth index, a spinster. Florence was probaby the wife of Lewis' brother. All three men were civil servants.

When Lewis Cozens enlisted on 1 October, 1914, he was a bachelor, 29 years old, living at 11 Albert St., East Melbourne and working as a clerk. His family, however, had moved by then to New Zealand, with his parents living at 15 Kensington Terrace, Wellington South. Lewis Cozens joined up and was placed in the newly formed 14th Battalion which, with the 13th, 15h and 16th battalion made up the 4th Brigade, under the command of Colonel John Monash. The battalion embarked for Egypt on HMAT Ulysses A38 on 22 December, 1914. 

On 25 April, 1915, they were part of the assault force landing at Anzac Cove. Lewis Cozens was by now a Lance Corporal. On 1 May, he was wounded, the report reading that he had 30 bullet wounds to his right arm and shoulder. It is a puzzling entry - thirty bullet wounds would suggest a very severe degree of wounding, yet the next entry is that he was made Corporal on 18 August, 1915, then received a severe wound on 8 October, which fracured his right arm. He was evacuated and sent back to Mudros, then on 22 August, sent on the Franconia back to England. Here he was admitted to King George's Hospital in Stamford Street, where he remained until 11 March 1916, when he was returned to Australia for discharge on board HT Sueris.

He was discharged from further service on 25 October, 1917. There is no record of him on the Ausrtalian Electoral rolls, so presumably, he went back to his family in New Zealand and continued to live with them. According ot the Public Member Trees which list him, he never married and the one entry on the Electoral Roll shows him in 1946 as a civil servant, living in Palmerston North.