In his youth he entered the navy, saw active service in many parts of the world, and rose to the rank of Lieutenant.

He came to Australia in January, 1812, and was appointed Surveyor-General.
Throughout his career in Australia, Oxley would seem to have won the friendship and respect of all he came in contact with.

Captain Charles Sturt, in the journal of his first expedition, wrote of him as follows:-- "A reflection arose to my mind, on examining these decaying vestiges of a former expedition, whether I should be more fortunate than the leader of it, and how far I should be able to penetrate beyond the point which had conquered his perseverance.

Only a week before I left Sydney I had followed Mr.Oxley to the tomb.

A man of great quickness and of uncommon ability.