Here’s a brief description of the Sept. 15, 1963, bombing by the Ku Klux Klan of a church in Birmingham, Ala., that left four girls dead. It was written by award-winning historian Taylor Branch in a book he dedicated to “students of freedom and teachers of history.”

That Sunday was the annual Youth Day at the Sixteenth Street Baptist Church. Mamie H. Grier, superintendent of the Sunday school, stopped in at the basement ladies’ room to find four young girls who had left Bible classes early and were talking excitedly about the beginning of the school year. All four were dressed in white from head to toe, as this was their day to run the main service for the adults at eleven o’clock. Grier urged them to hurry along and then went upstairs to sit in on her own women’s Sunday-school class. They were engaged in a lively debate on the lesson topic, “The Love That Forgives,” when a loud earthquake shook the entire church and showed the classroom with plaster and debris. Grier’s first thought was that it was like a ticker-tape parade. Maxine McNair, a schoolteacher sitting next to her, reflexively went stiff and was the only one to speak. “Oh, my goodness!” she said. She escaped with Grier, but the stairs down to the basement were blocked and the large stone staircase on the outside literally had vanished. They stumbled through the church to the front door and then made their way around outside through the gathering noise of moans and sirens. A hysterical church member shouted to Grier that her husband had already gone to the hospital in the first ambulance. McNair searched desperately for her only child until finally she came upon a sobbing old man and screamed, “Daddy; I can’t find Denise!” The grandfather helplessly replied, “She’s dead, baby. I’ve got one of her shoes.”

“The King Years: Historic Moments in the Civil Rights Movement” is a book that its author, Taylor Branch, a Pulitzer Prize-winning historian, said he never thought he’d write until he was persuaded to — by teachers.

Branch is best known for his trilogy of books on Martin Luther King’s life and the civil rights movement, which are meticulously researched and extremely long. (The paperback version of the first book, “Parting the Waters: America in the King Years 19541963, is 1,088 pages.) In a recent interview, Branch said that he had never anticipated writing a book for schools, but in his travels, teachers would repeatedly ask him for help in understanding and teaching the subject.

“I believe storytelling and things that are personal are the best point of entry for anybody, but it does make for a long and sprawling text,” he said. “And people ask me, ‘Do I regret doing all of that? And should I have written this short little book from the beginning?’ ”

Of course not, he said. Indeed, without the intimate knowledge he learned of the period during his many years of research, he couldn’t have adequately assembled a 190-page (in paperback) book that highlights the key moments of the King years, drawn from his trilogy. (The other two books in the trilogy are “Pillar of Fire: America in the King Years, 1963-65” and “At Canaan’s Edge: America in the King Years, 1965-68.”)

The result is a book that focuses on 18 turning points in history, including King’s first public address, the 1963 March on Washington, the 1963 church bombing and King’s Nobel Peace Prize in 1964. Chapter 18 is about King’s assassination in Memphis in 1968.

“There’s a lot of blood on the floor,” he said. “I had to leave out so much,” including information about King’s background and theology. “You have to pick episodic things that can stand for something larger.”

The real purpose of the book, he said, is to inform readers not only about history but also about citizenship.

“It’s about how a people who tenaciously applied and studied the best principles of patriotism and of democratic promise shifted the whole country in the direction of its own professed values,” he said. “It is about citizenship. It’s not just a good history, it’s a way of learning about citizenship that is all the more useful to young people.”

Branch said that young people learn about citizenship through the study of history, “which is why I wanted to answer all of the complaints from teachers who say we love the storytelling, but we can’t assign 800-page books.”

Teachers told Branch they wanted to have the heart and meaning of the story but not simply a summary. That’s why he includes moving parts of his trilogy that bring each moment he writes about to life.

Branch said he felt that it was important to help teachers, who have become “so beleaguered because the education system devalues history.”

“If history is the way we learn citizenship, then our focus on STEM and all these other things, it basically means it is going to be harder,” he said. “The teachers left over who are still doing this and trying to teach American history, which is about citizenship, then they need all the help they can get.

“I went around after the third King book, talking to teachers, history teachers. They said that if you are teaching American history in high school and junior high, your principal is going to get you to try to teach reading, not history. That’s how their school is evaluated. I’m not blaming the teachers. … Choosing to emphasize reading and math and leaving out citizenship is significant and a potential dangerous choice. … This will have long-range implications …

“It’s a knee-jerk reaction to think that science and math is everything because you still have to be a human being in the world and relate to other human beings,” he said.