For much of their music career, U2 has been trying to throw their arms around the world. But in the case of “One Tree Hill,” from 1987’s blockbuster The Joshua Tree, the Irish rockers were devoted to a more personal tragedy.

The hymn-like epic was mostly written about the funeral of friend and U2 employee Greg Carroll. Bono met Carroll on U2’s first trip to New Zealand, for the 1984 Unforgettable Fire tour. Wide awake in the middle of the night (due to jet lag), Bono went out on the town with some Auckland locals who wanted to show him the city. One of them was Carroll, a Maori man who had been hired as a roadie for the U2 concert. That night, Carroll and the others brought Bono up One Tree Hill (Maungakiekie in Maori), one of Auckland’s spiritually significant volcanic peaks.

Carroll also impressed Bono and the band with his work at the U2 gig. The twentysomething roadie had a few years of experience with New Zealand bands. His gentle but firm nature was obvious to U2’s members.

“He was so good, we asked him to come with us to Australia,” Bono said. “And he was still so good, we asked him to become a permanent member of our organization.”

So Carroll followed U2 to Australia and the U.S. and even Live Aid (he’s the man who hands Bono the microphone after his famous interactions with the crowd). At tour’s end, he flew with the band to Dublin, where he became a personal assistant to Bono. In the course of a couple years, Carroll not only became an important part of U2’s consortium but a great friend of the band’s lead singer and his wife, Ali Hewson.

In the run-up to recording a new album, which would become The Joshua Tree, Carroll was “researching locations for film for our next record and artwork for the cover,” according to Bono. “His goal was to direct and produce videos and films.”

Carroll was tragically stopped short of that goal when he was killed in a motorcycle accident in Dublin on July 3, 1986. He was taking Bono’s bike to his house on a rainy night, when a car pulled out in front of him. Carroll hit the side of the car and died instantly. Carroll was 26.

“His death really rocked us,” drummer Larry Mullen Jr. said in U2 by U2. “It was the first time anyone in our working circle had been killed.”

Bono had flown to Texas to sing with Willie Nelson, but hearing the news one hour after landing, flew back to Ireland. Bono, Ali, Mullen and other members of the U2 organization then flew with Carroll’s body to New Zealand, met his family and attended his funeral. Bono sang “Let it Be” and “Knockin’ on Heaven’s Door” in tribute to his late friend.

The singer and his band paid additional tribute to Carroll when writing and recording “One Tree Hill.” Bono reflected on his grief, while also referencing the peak he climbed the first night he met Carroll, in the lyrics: “The moon is up and over One Tree Hill / We see the sun go down in your eyes.” The frontman also wove in some political observations on the song’s second verse, referencing Chilean activist/folk singer Victor Jara.

“One Tree Hill” became the ninth track on The Joshua Tree. The final version features Bono’s only vocal take; he didn’t record another because he didn’t think he’d be able to make it through the song again. The track also was released as the LP’s fourth single in Australia and New Zealand, where it hit No. 1. U2 delayed performing the song live until the third leg of the tour for The Joshua Tree, because Bono thought his emotions would get in the way of his singing. It’s been sporadically played by the band since then, often at shows in New Zealand.

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"Trip Through Your Wires"

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