A watershed year of global unrest and upheaval, 1968 saw the invasion of Czechoslovakia, escalation of the Vietnam War, strikes and demonstrations by students and workers and the assassinations of Martin Luther King and Robert Kennedy.

In Hawaii, events such as a sit-in at Bachman Hall at the University of Hawaii at Manoa and strikes by ILWU pineapple workers and Honolulu Symphony musicians reflected the turbulent times, while, on a more quiet note, a groundbreaking new book turned to the past. “Shoal of Time: A History of the Hawaiian Islands,” by Gavan Daws, opened with the first visit of Captain Cook in 1778 and ended with statehood in 1959.

For its 50th anniversary, Daws has reissued “Shoal of Time” as an e-book with a new introduction. Total sales of the book to date, including the hardback and paperback editions, are approaching 250,000 copies, he said by phone last month.

The high volume of sales, which has made “Shoal” a best-seller over the years, seems all the more impressive when one learns that the idea and opportunity to write a history of Hawaii for the general reader came to Daws quite by chance.

“‘Shoal’ was my first book,” he said. “I came here from Australia in 1958, before statehood.” In the early 1960s, when he was a graduate student in the history department at UH-­Manoa, the communal phone in the hallway rang.

The caller was the editor-in-chief of MacMillan & Co., looking for someone who could write a Hawaii volume for the publishing house’s series of states’ histories. When he heard the advance was $3,000, about twice his annual stipend, Daws volunteered.

A year later, as the statehood population boom brought a surge in UH students, he was promoted to instructor.

“I taught primarily world civilization in the Varsity Theatre, seating 850 unwilling freshpersons, four sections of that per semester.”

Rather than derailing the writing of his book, his efforts to hold his students’ interest helped Daws develop a storytelling style that made “Shoal,” despite its deeply researched heft, an engaging read that received widespread critical praise.

Fifty years later, Daws says new histories and new voices are needed.

“History needs to be rewritten every generation,” he said. “There hasn’t been another general history of Hawaii with this timespan.”

Also nonexistent but needed, he said, is a general history of Hawaii encompassing 1959 through the present day, as “the rate of change compared with before statehood and the kind of change are just enormous.”

In reality, neither book is likely to be published today, said John Rosa, an associate professor of 20th-century history at UH-Manoa, for the reason that general histories have gone out of style among both academic and popular readers. Rather than large comprehensive volumes narrated by one voice, today there is an emphasis on selections from primary sources, including shorter readings taken from contemporary voices at the time.

Rosa himself has read “Shoal” many times.

“It’s extremely well-written, with a sense of humor and jest, moves quickly from chapter to chapter, and the research is comprehensive,” he said.

But Rosa doesn’t teach the book because, he said, it’s become outdated and problematic in many ways.

For example, “(Daws is) extremely critical of the alii and royalty,” Rosa said, “and some people see it as disparaging of Native Hawaiian alii and Hawaiians in general.” Current scholarship, he said, is re-examining their actions in “a different view, trying to understand where people were at at the time.”

Daws’ account of the Mahele, the land division in the mid-19th century, is cited as a case in point by Jonathan Osorio, professor of history and culture at the Hawai‘inuiakea School of Hawaiian Knowledge at UH-Manoa.

“Writing in the late ’60s, Daws would not have known that within a few years the Mahele would come to be the strongest symbol of Hawaiian loss to several generations of Hawaiian scholars and activists,” Osorio wrote in a 2005 essay on Daws and earlier historian Ralph Kuykendall.

“Nevertheless, his casual dismissal of the outcome of the Mahele as the result of the slowness of the chiefs to divide out their interests and the makaainana (commoners) being equally ‘dilatory’ is most unfortunate,” Osorio wrote.

“In his defense, that’s the way Daws writes,” Rosa noted. “He’s critical of everybody.”

Indeed, “Shoal” is scathing about the blatant racial prejudice of the land-grabbing sugar planters and missionary descendants who overthrew the Hawaiian monarchy, but, Osorio points out, while Daws is sympathetic to Native Hawaiians’ plight, that does not make up for his lack of understanding of their culture.

On the other hand, the book’s approach to Hawaii statehood is very positive, which also clouds its contemporary relevance, Rosa said. “It’s common now, since the 1990s, to be looking for much more critical histories of Hawaii that are not always celebrating Americanization.”

And although Daws writes with admiration and respect of the labor struggles, courage in World War II and political leadership of Hawaii’s Asian-Americans in the run-up to statehood, a simple outdated word — the use of “Oriental” to refer to them — may further put off today’s readers.

CASTING BACK over the long and productive career launched by “Shoal,” which includes 15 more books and stints as a scriptwriter for television and film, Daws said one of the most meaningful elements in his life has been music. “Kalakaua After Hours,” a hapa-haole song he co-wrote with Stephen Inglis about Honolulu vice in the 1940s, is performed in the forthcoming “Last Taxi Dance,” a short film by local director Brayden Yoder that will premiere at the Hawaii Theatre Center on Aug. 23.

What he does these days, mostly, is listen to music, Daws said. He used to perform it, too.

“In the early ’60s, people hung out at Greensleeves, a beatnik coffeehouse on Atkinson Drive, and an amateur folk singer without a mic would sing.” On Sundays, anyone could take the stage, and “I used to sing at those, they called them hootenannies.”

His favorites among his own books are a memoir that Jac Holzman, founder of Elektra Records, recruited him to co-author, and “Land and Power in Hawaii,” co-authored with George Cooper, “a truth-seeking missile,” as Daws described the attorney with whom he “dreamed up the book over pitchers of beer at the Kuhio Grill.”

He was happy to give up his academic career in 1989 and support himself as an author, he said. The royalties from his books “have somehow managed to stave off malnutrition for two people,” himself and Carolyn Yukiko, a Maui native to whom Daws has been married since 1962 and “is the best thing that ever happened to me.”

Asked if he might yet be up for updating “Shoal” or writing that general history that would take up from where it leaves off, Daws demurred.

“I’m 84. Everybody who writes a book writes from the time that they are living in, the air that they breathe.”

Reminded that he’s breathing the same air, “But I’m breathing it through my aged lungs,” he said, “and the oxygen is going to my aged brain.”

Daws’ perspective seemed to approach Rosa’s and Osorio’s as he envisioned what a new history would and should entail. It should cover, he said, “All that’s happened here since ‘Shoal’ and all the different ways of looking at what has happened: the Hawaiian Renaissance from the 1970s, all the different approaches of just being Hawaiian from Hawaii, so different from when I was breathing the air in the 1960s.”

Rosa, who was born in 1968, remembered hearing Daws speak about “Land and Power in Hawaii” at a Rotary Club lunch when he was a senior in high school.

“He’s a very engaging speaker and I heard about how the Democratic Party came into power and that was a great thing. But there were also all these inside deals, entirely in the public record.”

That got him thinking seriously about history, “and why it’s not dead and relates to the contemporary world,” Rosa said.

It may no longer be in vogue, but as a solidly researched history that’s readable, to boot, “Shoal of Time,” wrinkles and all, has not aged out.