Percy Fairless Mossop was born in Sunderland in 1886. He was a regular player in Port Adelaide’s first team from 1908 to 1910. A seaman by occupation, longer voyages may have prevented him from playing in subsequent seasons. A left half, he was described as a good defender and an excellent passer.
Percy Mossop enlisted in the AIF as early as September 2nd 1914. He was single and 28 years old. With the 10th Battalion he was amongst the first ashore at Gallipoli on April 25th 1915. He was twice wounded at Gallipoli, losing his right ear on the second occasion, before being evacuated sick to Egypt in September. After switching to the 50th Battalion he served in France and England from 1917 until the end of the war, taking his discharge in Adelaide in February 1919.