LEXINGTON, KY. ? Thomas D. Clark, Kentucky’s most prominent historian, has had a distinct advantage over his colleagues: His life has spanned nearly half the state’s history.

Clark, declared the state’s historian laureate for life in 1990, celebrated his 100th birthday on earlier this month, spending it like he has many other days — exhorting an audience about education, a personal passion.

“We haven’t reached the top of the mountain in education by any means,” Clark said in a recent interview. Nevertheless, “we have made progress. The school system is not the school system of the 1950s by any means.”

Clark’s prominence — not to mention longevity — as a historian gives him more standing than most for addressing education and other important subjects, colleagues say.

Being a historian “pushed him toward an understanding of what a blight on the South and the state neglect of education had been,” said Robert Sexton, the executive director of an education advocacy group who met Clark while a graduate assistant.

“He no doubt would have been an advocate, no matter what his academic field,” Sexton said. But being a historian “gave him, I think, more passion about it.”

The University of Kentucky has been Clark’s base for three-fourths of his life as a scholar, teacher, researcher, conservationist and preservationist.

“Dr. Clark is Kentucky history,” Patsy Todd, wife of the university’s president and a former Clark student, said at a birthday celebration. “He is a remarkable man whose knowledge and kindness have been felt by so many.”

Clark’s birthday capped a week of centenary honors and tributes, including the release of a volume of essays on Clark’s many facets — Southern historian and writer, agrarian and preservationist, among others.

The son of a Mississippi cotton farmer, he arrived at the University of Kentucky as a graduate student in 1928. He ultimately decided to put down roots and delved into Kentucky history.

Clark said he remembered being immediately struck by the sectionalism that defined his new state’s politics and, in his opinion, continues to plague and retard it today.

Clark said that is reflected in the state’s 1891 Constitution, which is overburdened with minutiae, and its division into 120 counties, more than all other states except Texas and Georgia.

The result, he said, has been a squandering of natural resources, too little appreciation of education and a wasteful duplication of government. “One hundred twenty counties waste enough money every year to maintain a major university,” Clark said.

Living through an era provides important insights for a historian, said James C. Klotter, the current state historian and professor of history at Georgetown College.

“Re-creating a place in time from newspapers, memoirs, letters, diaries, oral histories and other primary sources can get us close to understanding an era,” Klotter said. “But living in a time, as Dr. Clark has done, also helps a historian get a feel for the period and its people in a way those other sources may not.”

Clark not only studied Kentucky history. He also saved part of it, stopping the state librarian, who had run out of storage space, from selling truckloads of state records as scrap in 1936.

In a state that had but a handful of libraries at the time, Clark persuaded policy makers to establish a decent state archive, and he almost single-handedly built the special documents collection at the University of Kentucky’s library.

“Many historians realize the need to preserve records, but Dr. Clark did something,” Klotter said. “

He did not sit in a comfortable office at UK, resting on his considerable laurels, but instead went out and fought the hard, dirty fights to preserve the state’s past in secure facilities.”