Influential conservative media entrepreneur Andrew Breitbart died suddenly Wednesday night of "natural causes." He was 43.
Breitbar's family said he collapsed while he was taking a walk near his home in Brentwood, Calf.
While he had suffered from heart problems a year ago, Breitbart's death is shocking to many.
"We have lost a husband, a father, a son, a brother, a dear friend, a patriot and a happy warrior. Andrew lived boldly, so that we more timid souls would dare to live freely and fully, and fight for the fragile liberty he showed us how to love," wrote Larry Solov, the president of Breitbart.com, LLC.
He was known as a "force" in the conservative cause and was behind the investigations that led to the resignations of former Rep. Anthony Weiner of New York and former U.S. Agriculture Department official Shirley Sherrod.
CBN News' David Brody interviewed him at his home in April 2010.
"To be at the forefront of what I believe is a righteous mission, which is an extension of our founding fathers mission, which is as gratifying a place as one could be. It feels overwhelming. It feels like a privilege, and I wouldn't have it any other way," he told Brody.
In his blog, The Brody File, Brody reflected on his time spent with Breitbart a few years ago.
"Andrew definitely had a zest for life. I remember him touring me around L.A. taking me to places he grew up and had the best memories. He was always on the go, never slowing down," he said.
"His brain was a non-stop treasure trove of ideas and opinions," he conintued. "I'll always remember how full of life he was and how passionate he fought for the causes he believed in. I'll miss him."
Condolences for his family have poured in from the media and political world.
"RIP 'O Mighty Warrior!" Texas Gov. Rick Perry said in a message on Twitter.
The Republican presidential candidates also tweeted their condolences.
After learning of his death from reporters at a rally in Dalton, Ga., former Sen. Rick Santorum said Breitbart was a "powerful force."
"He will be what a huge loss. for our country and certainly for the conservative movement and my prayers go out to his family," Santorum told reporters. "I'm really sorry to hear it."
Mitt Romney posted to Twitter: "Ann and I are deeply saddened by the passing of AndrewBreitbart: brilliant entrepreneur, fearless conservative, loving husband and father."
Newt Gingrich tweeted: "Andrew Breitbart was the most innovative pioneer in conservative activist social media in America. He had great courage and creativity."
Breitbart leaves behind his wife Susannah Bean Breitbart, and four children.