Who is Sam Johnson from Lyndon Johnson and the American Dream and what is their importance?

Sam Johnson was Lyndon's father. He was a small-time farmer, who also dabbled in real estate and cattle speculation. As a result, income to the household was sporadic at best. Sam was Rebekah's opposite, and he is described as having been loud, vulgar, and a heavy drinker. He is also said to have been a great storyteller and was well-liked by everyone.