I believe it was Lorne Green!
He was not only "Pa" on Bonanza, but he sang the hit song "Ringo", based on a real-life character.
Dan Blocker was a real strong guy in real life. Before he became a famous movie star, they said he would install the real axel in a car without using anything to jack up the axle! Let me tell you, that would not be an easy thing to do! That is a feat of incredible strength.
Michael Landon was the youngest son, who later starred in Little House on the Prairie.
Bonanza was one of the westerns we grew up watching. All of them (Lone Ranger, Gun Smoke, The Rifleman, etc.) all always had a moral message embedded in the plot, and I think growing up watching them made us better folks. I worry about the current generation.