His family migrated to Australia in 1914, settling in Stanthorpe, Queensland. His family were orchardists, and his first break came as an artist when he was working in his family’s orchard and drew a cartoon of an angry farmer venting his his fury in receiving – not the expected cheques – but a bill for dumping his fruit because of a glut in the Brisbane market. To his surprise it was published in the Qld Farm Bulletin, and they sent him 10 shillings which was more than his father paid for a whole week's work.
In 1918 he moved to Brisbane with 5 pounds, a folio of his drawings and a bike. Curtis worked as an illustrator, cartoonist, architectural draftsman, camouflage officer and was appointed Official War Artist in 1945. The Australian War Memorial holds more than 200 of his works. His documentation of the building of the Sydney Harbour Bridge is widely admired.