Ahern was the second of five children. His father was the music director for their Catholic parish. At the age of twelve, Ahern was hospitalized with a severe asthma condition. His father gave him a guitar. He strummed his way through school, and the folk era. When records were played at school sock-hops, Ahern convinced the school administration to purchase equipment so a school band could play live. At St. Mary's University, he played Junior Varsity football as well as music. Ahern played on a CBC network summer replacement television show called Singalong Jubilee. Anne Murray auditioned for the show in 1964, and Ahern played guitar for her. She was rejected, but two years later was invited back to audition again, and hired. Ahern had by that time become the Music Director. Ahern formed his own band named "Brian Ahern and The Offbeats". They were a critical and popular success on Frank's Bandstand, the Halifax segment of the national show Music Hop. Ahern was music director of Frank's Bandstand and hired Anne Murray periodically on the show beginning in 1965. The band also performed as the "Nova Scotians". Ahern also had a third band called The Badd Cedes, later renamed Chapter V. After getting signed to Verve/Folkways in New York in 1967, they recorded a number of demos at the CBC in Halifax and relocated to Toronto to record several sessions for the label.
Toronto years
While in Toronto they released their only single, 'The Sun Is Green'/'Dolly's Magic' in 1967. Ahern wrote both songs and sang "Dolly's Magic", which became a hit. They promoted the record with appearances on Canadian television including CBC-TV's 'Music Hop'. After the initial buzz of the single wore off, the group relocated – this time to Ottawa – and added Bruce MacFarland on guitar. They changed their name to Elizabeth but failed to make any headway and split up by 1969. Despite the fate of his own band, Ahern began to have success as a producer. As musical director of the Singalong Jubilee, Ahern advised Murray that she should move to Toronto and record a solo album. Murray's first album, What About Me, was produced by Ahern in Toronto and released in 1968 on the Arc label. Murray's debut album was on the Canadian Arc label, titled What About Me. The lead single was the cut of the same name, was written by Scott McKenzie, and was a sizable Canadian radio hit. The project was produced by Ahern, and covered songs by Joni Mitchell, Ken Tobias, and John Denver. In February 1969, Ahern recorded Neil Young's Live at the Riverboat 1969, which was taken from a series of shows at the Riverboat Coffeehouse in Toronto. After a year-long stint on Arc, Murray switched to Capitol Records in 1969 to record her second album with Ahern, This Way Is My Way, which was released in the fall of the same year. This album featured the single that launched their successful career, "Snowbird", which became a No. 1 hit in Canada. "Snowbird" became a surprise hit on the U.S. charts as well, reaching No. 8 on the Billboard Hot 100 chart in 1970. It was also the first of eight No. 1 Adult Contemporary hits for Murray. The song led to Murray being awarded the first Gold record ever given to a Canadian artist in the United States.
Los Angeles years
When Emmylou Harris was contracted to Reprise, Ahern was specifically assigned to produce her records. Harris' Reprise debut Pieces of the Sky was released in 1975. Ahern and Harris assembled many of the musicians who had played on Gram Parsons solo albums, including James Burton, Glen D. Hardin, and Ron Tutt for the sessions. Ahern had signed Texas songwriter Rodney Crowell to his publishing company prior to starting work with Harris, and introduced Harris to Crowell's songs. Harris would record a number of Crowell's songs on her Ahern-produced albums including "Till I Gain Control Again," "Leaving Louisiana In The Broad Daylight," "Ashes By Now," "You're Supposed To Be Feelin' Good," "Angel Eyes," and "I Don't Have To Crawl." Ahern produced all of Harris' Warner Bros/Reprise recordings through 1983's White Shoes, including #1 albums Elite Hotel and Luxury Liner.
On 9 January 1977, Ahern and Harris were married at his home in Halifax, Nova Scotia. They had one daughter together in 1979. Ahern and Harris divorced in 1984. While in Los Angeles, Ahern also produced Rodney Crowell's debut album Ain't Living Long Like This, Johnny Cash's Silver, and two albums by Mary Kay Place.
Nashville years
In Nashville he produced Ricky Skaggs, Marty Robbins, and George Jones. Ahern continued to produce Emmylou Harris, the last recording being All I Intended to Be in 2008.
Honours
On December 28, 2019, Governor General Julie Payette announced that Ahern had been appointed as a member of the Order of Canada.
