New Australia was a late-19th Century intentional community experiment in Paraguay, the brainchild of English-born Australian labor leader William Lane.

On July 16, 1893, on a Sunday afternoon one week after a large farewell gathering (10,000 people on July 9) in Sydney's Domain, the Royal Tar sailed, arriving at Montevideo, Uruguay on September 13, and William Lane and his hundreds of followers worked hard to establish the New Australia and Cosme utopian socialist settlements near Villarrica, Paraguay (he called it "socialism with a small 's'").

Within just a few days of setting sail from Sydney Harbour there were petty squabbles among some of the emigrants. In Paraguay, disputation became more frequent and Lane became increasingly authoritarian. The colony split in its first year and Lane and his "Royalists" as they were jokingly called left "the Rebels" and founded another colony which they called Cosme. Some of Lane's most fervent supporters also abandoned the project when Lane started crediting God with some of his actions.

Descendants of some of the 600 settlers still live there.