The first recording of the D'Irlam family is their arrival in Hull in 1069, possibly from Scandinavia. They leased from the Crown approximately 3/4 of Lancaster, the rest of Lancaster being held by the Knights Templar. The family faded away around 1745 when they supported the Jocobites, which King George II was not too pleased. About 1770 Elisa D'Irlam immigrated to America and many of her descendants live in Buffalo but pronounce their name as Dirlam.
The earlist arrival in Australia, I know about is Isaac Irlam aged 21 in December 1858 in Victoria on the ship Tasmania, with Jessie Irlam (21), Alex Irlam (2) and Jane (1)
The Irlam's in Burra SA also had an early descendant arrival around this time but I'm not sure of the precise reason for his travel. I have heard that he ran away from home and worked his way to Australia, the other account is he got a free ticket after being found guilty of Bigamy.
Other early settlers were W.M. Irlam (25), Israiel Irlam (20) and Susanna Irlam (19) in August 1863 on the ship Southern Ocean in Victoria. Jacob Irlam (19) also travelled to Victoria on July 1862 on the City of Melbourne.