In 1968, Van Morrison and his wife, Janet, were living in Cambridge, Massachusetts. He’d made one album, Blowin’ Your Mind, and one indelible single, “Brown Eyed Girl.” But late in 1967, after Morrison and Bang Records chief Bert Berns got into a shouting argument, Berns fell over dead. Morrison wanted out of the contract he signed with Berns, but Berns’ mobbed-up business partners weren’t willing to just let him walk. It took a sack of $20,000 in cash, delivered to a warehouse in the dark of night by a Warner Brothers executive, to get him free. While the contract situation was hanging over his head, Morrison was working on new music—music that would eventually become the legendary album Astral Weeks.

The making of that album is only one of the Boston stories told in Astral Weeks: A Secret History of 1968 by Ryan H. Walsh. In addition to Morrison, we meet an enigmatic guru named Mel Lyman, who presided over a commune in Boston’s Fort Hill neighborhood, published a newspaper called the Avatar, was deeply influential in the city’s counterculture, claimed to be God, and may or may not have died a decade later. We’re present at the Velvet Underground’s historic residency at the Boston Tea Party, and the less-successful attempt to hype the local music scene under the name “the Bosstown Sound.” We visit the set of an experimental public television show called What’s Happening, Mr. Silver? and influential rock radio station WBCN. We tag along at an odd modern-day meeting between the author and musician (and former WBCN DJ) Peter Wolf, who says he has tapes of a show at which Morrison, his longtime friend, played some of the Astral Weeks songs for the very first time. And we’re there the night James Brown plays a televised concert in the wake of Martin Luther King’s murder that’s credited with keeping the lid on the city.

The Brown story is often portrayed as a magnanimous gesture by a star who wanted to do something for his people. The reality is something else again. Brown was scheduled to play Boston Garden on April 5, the night after the King shooting. Officials feared what might happen with so many black people in one place, but they also feared what might happen if the show were canceled. So the idea came about to televise it, thereby keeping people indoors and off the streets. Brown hated the idea at first; TV would lower the attendance and his take of the proceeds. The city agreed to pick up the cost of lost earnings from ticket sales, which turned out to be $60,000. (Mayor Kevin White ended up having to go to a group of old-line Boston financiers for a handout to cover it.) The concert nearly went bad when audience members started jumping on stage, but Brown managed to get the fans back under control, and ended up keeping Boston peaceful while other cities were burning. Years later, White would say it was definitely worth the money.

Although Van Morrison had woodshedded his new songs with a group of local musicians, only one of them ended up playing on Astral Weeks. Producer Lewis Merenstein rounded up a group of bigtime professionals to play; one of them, guitarist Jay Berliner, walked into the first Astral Weeks session after spending the afternoon recording jingles for skin cream and potato chips. Another, bassist Richard Davis, said that none of the musicians had ever heard of Morrison and he never spoke to them, staying in the vocal booth with his guitar the whole time. Because the musicians were all jazz players, they were able to improvise at the direction of Morrison and Merenstein; the album came together in three sessions over several weeks.

You don’t have to know anything about Boston to read Astral Weeks, although it might enhance your enjoyment if you do. For example, Marsh Chapel at Boston University figures in several scenes; only after I finished the book did I remember that I attended a wedding there many years ago. At a time when we’re overdosing on memories of 1968, Astral Weeks: A Secret History of 1968 is on ground that few other histories of that fabled year have covered.

(Postscript: in a Twitter exchange we had over the weekend, Ryan Walsh reminded me that an early edition of the Grateful Dead was heavily inspired by the Jim Kweskin Jug Band. Kweskin was an associate and sometime-bandmate of Mel Lyman’s, and lived at Fort Hill. So the Dead has something to do with the 1968 Boston story, albeit peripherally.)