It's Juneteenth, also known as "Freedom Day" — commemorating the ending of slavery in the United States. It was on June 19, 1865, when union soldiers arrived in Galveston, Texas, to announce slavery had been abolished. That was two years after President Abraham Lincoln issued the Emancipation of Proclamation. On Second Thought looked at Juneteenth traditions and history with Daina Ramey Berry. Berry is professor of history and African and African diaspora studies at the University of Texas at Austin . She's also author of four books that detail the history of slavery, including "The Price for Their Pound of Flesh."