In early 1967 he joined the final lineup of the Esquires. He moved to Toronto that summer to form The Flying Circus with Marty Fisher and Gordon MacBain former Bobby Kris & The Imperials members and Neil Lillie ex-Tripp member. The group recorded some material in late 1967 (which remains unreleased) before changing its name to Olivus in the spring of 1968, by which time Lillie (who changed his name to Neil Merryweather) had been replaced by Dennis Pendrith from Livingstone's Journey. Olivus opened for The Jimi Hendrix Experience and Cream in April 1968. That summer Cockburn broke up the band with the intention of going solo, but ended up in the band 3's a Crowd with David Wiffen, Colleen Peterson, and Richard Patterson, who had been a co-member of The Children. Cockburn left 3's a Crowd in the spring of 1969 to pursue a solo career.
Cockburn's first solo appearance was at the Mariposa Folk Festival in 1967, and in 1969 he was a headliner. In 1970 he released his self-titled, solo album. A single, "Going to the Country", appeared on the RPM Top 50 Canadian Chart.