Bumpers, a Democrat, died at his home in Little Rock after suffering from Alzheimer's disease and a broken hip.
An emotional William Bumpers told CNN Saturday that principle is what mattered most to his father.
"He was a man of policy and honor and not politics," Bumpers said. "A lot of the stances he took were not politically expedient or popular back home, but they were the right positions to take."
Bumpers served as the 38th governor of Arkansas from 1971 to 1975, and represented The Natural State in the U.S. Senate from 1975 to 1999. He is perhaps best known for defending Clinton during his impeachment trial in the Senate, when he called the controversy over the Lewinsky affair "a sex scandal" and not an impeachable offense.
"The American people are now and for some time have been asking to be allowed a good night's sleep," Bumpers told the chamber
. "They're asking for an end to this nightmare. It is a legitimate request."
"For more than 40 years, Hillary and I cherished his friendship," Clinton said in a statement Saturday afternoon. "I am grateful that his advice made me a better governor and President, and that we laughed at each other's jokes even when we'd heard them before. And I'm grateful that he welcomed Hillary to Arkansas and supported her in Washington."
"I loved him. I loved learning from him and laughing with him. I will miss him very much," he added.
A progressive voice in Arkansas
Bumpers was born on August 12, 1925, in Charleston, Arkansas, according to the Library of Congress
. A public school attendee, Bumpers attended the University of Arkansas, Fayetteville, before leaving college to serve in the Marine Corps during World War II. After the war, he graduated from the University of Arkansas and earned a law degree from Northwestern University.
He then moved back to Charleston, where he became the city's attorney, a position he would hold from 1952 to 1970.
While serving as city attorney in the 1950s, he convinced the school board to accept the Brown v. Board of Education
ruling integrating public schools, his son said. At the time, Arkansas's governor, Orval Faubus, was making national headlines for his outspoken opposition to integration
, famously calling on the National Guard to defy a federal order to integrate a high school in Little Rock.
"He told the school board they had to integrate. It was the right thing to do, and he convinced the school board to vote for integration," William Bumpers said. "Charleston was the first school district in the whole confederacy to fully integrate. He was very proud of that."
Bumpers entered politics a decade later at the urging of his father, William Rufus Bumpers, who told his son that politics was a "noble profession," William Bumpers said.
As a long-time political force in Arkansas, Bumpers befriended and served as a mentor to Clinton beginning in the mid-1970s. Bumpers himself was often considered a potential presidential and vice presidential candidate, though he never sought either office.
'A hero and a statesman'
Reaction to Bumpers' death began to pour in on Saturday.
Arkansas Gov. Asa Hutchinson, who unsuccessfully challenged Bumpers in a 1986 Senate race, called his onetime opponent a "master storyteller."
"In my first statewide race, Dale took me to school on Arkansas politics. He was a master storyteller, and his stump speaking was impossible to beat," Hutchinson, a Republican, said in a statement. "From that first campaign in which we were competitors, to the time we served together in Congress, I have admired Dale for his skill, heartfelt convictions and his sense of humor. After he retired, he continued to set an example of civic responsibility and good will during a time of increased partisanship in our nation. We will all miss Dale."
Former Arkansas governor and Republican presidential candidate Mike Huckabee -- who ran and lost against Bumpers in a 1992 Senate race -- issued a statement on his campaign website praising his predecessor
"Senator Bumpers was extremely helpful to Arkansas and to me personally. Betty and the family are in our prayers," Huckabee added on Twitter.
Other members of the Arkansas political community took to social media to share their thoughts on Bumpers.
"He was a statesman who served Arkansas with distinction. His legacy is one of dedication to this state we all love," tweeted Rep. Bruce Westerman, a Republican.
"Arkansas lost a hero and a statesman last night with the passing of Senator Dale Bumpers. Our thoughts and prayers go out to his family," the Arkansas Democratic Party said on Twitter.
Bumpers is survived by his wife, Betty, and his children, Brent, William and Brooke. Funeral arrangements have not yet been finalized.