Former US President Jimmy Carter was the first of four US presidents to speak at the Civil Rights Summit held at a presidential library in Austin, Texas on Tuesday. The three others are Barack Obama, Bill Clinton and George W. Bush.

The event is organized by the Lyndon B. Johnson (LBJ) Presidential Library to commemorate the 50th anniversary of the Civil Rights Act, which was signed into law by Johnson in 1964.

In an internet live-broadcast interview with the director of LBJ library Mark K. Updegrove Tuesday night, the 39th president of the United States touched on an array of issues including inequality between men and women, black and white people, and even gay marriage.

The nearly 90-year-old ex-president, looking in good health, recalled how his being raised up by African-American caregivers and playing with his black neighbors' children shaped his life.

He also recollected how he helped to break the logjam in Camp David peace talks in 1978 and broker the Israel-Egypt Peace Treaty, a cornerstone of peace between the two countries and in the Middle East.

Obama is scheduled to give a keynote speech at the summit on Thursday. Clinton and Bush will speak on Wednesday and Thursday, respectively.

The Civil Rights Act of 1964 is a landmark piece of civil rights legislation in the United States that outlawed discrimination based on race, color, religion, sex, or national origin.

It barred unequal application of voter registration requirements and prohibited racial segregation in public places.