On 15 June 1862, at the age of 16, Seddon decided to emigrate to Australia, on the SS "Great Britain". He later provided his reasoning: "A restlessness to get away to see new, broad lands seized me: My work was irksome. I felt cramped." He entered the railway workshops at Melbourne, Victoria. He was caught by the gold fever and went to Bendigo, where he spent some time in the diggings. He did not meet with any great success. In either 1865 or 1866, he became engaged to Louisa Jane Spotswood, but her family would not permit marriage until Seddon was financially secure.