January, President-elect Barack Obama and his family will make history, becoming the first African-American first family to move into the White House -- a house with a history of slavery. In fact, the legacy of American presidents owning slaves goes all the way back to George Washington.

Twelve American presidents owned slaves and eight of them, starting with Washington, owned slaves while they lived in the White House. Almost from the very start, slaves were a common sight in the executive mansion. A list of construction workers building the White House in 1795 includes five slaves - named Tom, Peter, Ben, Harry and Daniel -- all put to work as carpenters. Other slaves worked as masons in the government quarries, cutting the stone for early government buildings, including the White House and U.S. Capitol. According to records kept by the White House Historical Association, slaves often worked seven days a week -- even in the hot and humid Washington summers.

In 1800, John Adams was the first president to live in the White House, moving in before it was finished. Adams was a staunch opponent of slavery, and kept no slaves. Future presidents, however, didn't follow his lead. Thomas Jefferson, who succeeded Adams, wrote that slavery was an"assemblage of horrors" and yet he brought his slaves with him. Early presidents were expected to pay their household expenses themselves, and many who came from the so-called"slave states" simply brought their slaves with them.