Between 1936 and 1943, Morton recorded 93 78-rpm records of his songs, accompanying himself on an acoustic guitar for most tracks, for Columbia's Regal Zonophone label. On some later tracks, he was accompanied by his band, The Rough Riders, and a female singer 'Sister' Dorrie (real name Dorothy Carroll). In 1943, he left Columbia following a dispute with Arch Kerr, the Record Sales Manager, probably over the company's reluctance to use The Rough Riders. He was billed as 'The Yodelling Boundary Rider' on records, though he apparently didn't approve of the name.
In 1949 and 1950, he recorded more sides in Sydney and possibly New Zealand. These were released on the Rodeo and Tasman labels; some songs were probably recorded at the instigation of Ralph Peer, who visited Sydney in 1949 and met Morton.
Morton, in his career, capitalized on American cowboy and "Wild West" images, and was sometimes billed as "The Singing Cowboy Sensation," performing for rodeos, and singing in a yodeling style that drew heavily on those of American singers such as Jimmie Rodgers. His yodelling was influenced by Rodgers, Goebel Reeves and the British Alpine yodeller, Harry Torrani. Although Morton chose to sing in an American (rather than Australian) accent and sang many songs with American subject matter, several of his recorded songs (such as "The Ned Kelly Song," "Beautiful Queensland," and "Murrumbidgee Jack") feature Australian themes. ("Beautiful Queensland" was a simple re-write of W. Lee O'Daniel's "Beautiful Texas", however.)
During the 1930s and 1940s, he gradually 'Australian-ised' many of the songs he wrote. This approach was followed by other Australian country artists who followed in his footsteps, such as Buddy Williams and Slim Dusty, leading to a particular genre of country music - the Australian bush ballad, which was also influenced by the turn-of-the-century poetry of 'Banjo' Patterson and Henry Lawson.
From 1950 to 1959, Morton was in Canada and the United States. He toured with Pee Wee King in 1952 and recorded in Nashville in March 1953. He claimed to have toured for six months as an opening act for Hank Williams, but this is extremely unlikely, though he may have met Williams in late 1952 through Oscar Davis, who was Morton's manager and Williams's last manager.
Morton toured Canada and the United States as a stage hypnotist, memory expert, whip cracker and sharpshooter, and was associated for some time with the Canadian country singer, 'Dixie' Bill Hilton. He returned to Australia in 1959 with a Grand Ole Opry show, featuring Roy Acuff, the Wilburn Brothers and June Webb, but the show was not popular with Australian audiences and the tour had to be called off. As a sharpshooter, he was legendary, admitting to only one miss: He was about to shoot a cigarette out from between a man's lips when, at the moment he pulled the trigger, the man moved his lips, tilting the cigarette upward. The bullet nipped his nose and, recounted Morton, he was called "Nick" after that. He did a memory act, asking the audience to give him 100 words. He'd recount them back in order, "forgetting" one of them around the 50th word only to suddenly remember the word when he was almost finished his act.
Morton continued to record during the 1960s and 1970s, but increasingly showed an interest in acting. He appeared in Australian television shows and feature movies (such as "We Of The Never Never"). He was the first inductee into Australia's country music Roll of Renown in 1976, recognising his pivotal role in the development of country music in Australia and New Zealand.