Historian Leland Dewitt Baldwin was born on November 23, 1897, in Fairchance, Fayette County. Baldwin was the son of Harmon Allen and Etta Weatherly Baldwin. Baldwin's minister father was a well-known Methodist evangelist at conferences throughout the Ohio Valley. Baldwin's father was also a Prohibition Party ticket possibility for the vice-presidential slot. As part of his religious mission, Baldwin's father wrote a number of theological texts, including Lessons for Seekers of Holiness, The Indwelling Christ, and Holiness and the Human Element. So at a young age, Leland Baldwin was given a powerful example of writing. Biographer Edward Chester quoted Baldwin saying, "Papa used to write on a chair while sitting on the floor, so I fixed myself in the same manner and began writing along with him in an old copy book." They would, however, come to differ in their religious beliefs.

Another influence in Baldwin's life was travel. Baldwin traveled all around the United States, but he never stayed anywhere twice. This contributed much to Baldwin's intellectual development. Because he moved around so much, Baldwin was able to learn about other people's cultures and histories. He held many blue-collar jobs in his lifetime and became familiar with the average working class. This helped him accurately convey how this class felt at major times in history. This is one of the ideas Baldwin focuses on in his book Whiskey Rebels: The Story of a Frontier Uprising (1939). Because he traveled so much in his younger life, Baldwin tended to travel often in his adult life. Baldwin spent time in North Africa as well as Western Europe.

While Baldwin was not traveling, he attended Greenville College in Illinois beginning September 1915. He was very involved with the debate team throughout his college years. Edward Chester described some of Baldwin's college pranks, and Baldwin said in reply "I have been looking over my Greenville album and it reminds me of what a downright ass I was. I hope that I have better control of myself now." One of the pranks involved Baldwin rigging an alarm clock to make it go off under the seniors' table at dinner. Despite being very critical of himself, Baldwin worked hard and graduated from college in 1921.

From there, Baldwin attended the University of Michigan in 1922. He only attended college during the summer, because during the regular school year he became a teacher at Miltonvale College in Kansas. This hard life did not hold him back; he graduated with a Master of Arts from the University of Michigan in 1923. While working on his PhD, Baldwin took on many teaching jobs, including teaching at Allegheny County's Har-brack and Crafton High Schools. During that time, in 1927, Baldwin married Ruth Glosser. Again, all of his hard work paid off, and in 1932 he earned his Doctorate in History from the University of Pittsburgh.

As a professional working in secondary education, Baldwin wrote, "What I have Learned in Seven Years of Teaching High School History," in a 1930 issue of Education. In the essay, Baldwin stated, "To begin with, I am one of that preponderating majority of high school teachers who do not like their work." He goes on to explain how he started teaching high school. "When I left college my desire was to teach history in college, but I needed money, so consequently took the highest paid position I could find...I have remained ever since, because I am in a rut and because I cannot afford to continue myself to a college salary."

After earning his Doctoral degree in 1932, Baldwin became the Librarian and Research Associate in the Western Pennsylvania Historical Society. Other than teaching, Baldwin had many opinions, including political, on what was going on around him. When Baldwin was younger, he tended to side with the Republicans. He voted for Warren Harding in the 1920 Presidential race, and he was quick to judge him later on. In his book The Stream of American History (1952), Baldwin called Harding an incompetent president and opined that only U. S. Grant had been a worse president. Baldwin was able to publish more of his works when he became the first Editor of the University of Pittsburgh Press. During his tenure, from 1936 to 1939, he supervised many publications. Among them were his own books: Pittsburgh: The Story of a City (1937) and Whiskey Rebels: The Story of a Frontier Uprising (1939).

After he published Whiskey Rebels, Baldwin drew more notice from leading American historians. Critic Homer C. Hockett stated, "Professor Baldwin has given us the first adequate account of a famous incident, based on study of virtually all pertinent material." This book was Baldwin's first breakdown of the American democratic process.

Not all of his books were liked though, reviewer Max Savelle stated, concerning The Meaning of America: Essays Toward an Understanding of the American Spirit (1956), "Professor Baldwin's book, in spite of its title and subtitle, hardly makes the historical reality and nature of America's meaning and the 'American Spirit' clearer than they have been....Surely there is no fixed, absolute, and unchanging historical 'meaning' of any society or civilization, so long as it is alive. Any such 'meaning' would signify cultural death."

In 1942, Baldwin enlisted in the U.S. Air Force. Although he never took part in combat, Baldwin did win many service awards, including the EAME Theater Ribbon with four battle stars. He also received the Legion of Merit and five Overseas Service Bars.

Baldwin is considered to have influenced the study of history today. Baldwin's definition of history, as stated in the beginning of his book The Story of the Americas (1943), "is the record of a certain species of migratory animals called Homo sapiens — of their impact upon each other and upon their natural surroundings, and of their search for the meaning of the universe." In his earlier books, Baldwin provided the readers with colorful treatment of historical events. He also described these in a solid narrative framework. Because Baldwin wrote like this, he made history seem to come alive. He was one of the few American historians who saw a relationship between fiction and history. Baldwin also stated in the Preface of The Story of the Americas that "there are two ways of writing history: one is intended for the professional historian, the other for the delectation and information of the general reader. This book is not for historians. Rather it is an attempt to paint an impressionistic picture of the surging racial frontiers..." Baldwin stated that he wrote for the public, not for other historians.

Leland Baldwin died on March 6, 1981, at age 83, after heart surgery. Even though Baldwin is gone, he left a legacy for the chronicling of Western Pennsylvania history. Edward Chester of the Pittsburgh Post Gazette stated that "Mr. Baldwin's history project helped motivate the interest of Pittsburgh's leaders in the development of the historic Point [State Park], which in turn was the foundation stone for Renaissance I. If for no other reason, that would have insured Mr. Baldwin's place in the history of the city about which he wrote so much and knew so well." Chester, a professor at the University of Texas at Arlington, said: "Leland Dewitt Baldwin...was perhaps that most brilliant and prolific historian that Western Pennsylvania has ever produced."