No Civil Rights timeline would be complete without the key events of 1965, from the confrontation at the Edmund Pettus Bridge in Selma, Alabama, to the passage of the Voting Rights Act.

Medicare appears nowhere on the list. Yet, in its vast scope and the immediacy of its impact, Medicare ranks among the most important Civil Rights achievements in U.S. history.

By threatening to withhold federal funding from any hospital that practiced racial discrimination, as required by Title VI of the Civil Rights Act, passed in 1964, Medicare forced the desegregation of every hospital in America virtually overnight.

Amazingly, almost no one noticed.

"It was kept quite secret," says David Barton Smith, a professor emeritus of healthcare management at Temple University. "The White House kept a lid on it."

Unlike the integration of restaurants, public transportation and schools, there were no confrontations between marchers and police, no chanting mobs or desperately ill patients turned away.

"It's absolutely incredible how little organized resistance there was," says Theodore Marmor, emeritus professor of public policy at Yale University and a key health policy adviser during the Johnson administration.

Before the passage of Medicare and Medicaid, Smith says, the healthcare system was tightly segregated. Hospitals in the South complied with Jim Crow laws, excluding blacks from hospitals reserved for whites or providing basement accommodations for them.

"There were a lot of black communities in the South that had basically no access to hospitals," says Smith. "Most of the black births in Mississippi were at home. The infant and maternal mortality rates were hugely different for blacks and whites because of that."

In the north, segregation was more subtle. Black physicians couldn't get privileges to practice at hospitals dominated by whites, and white physicians were pressured to send black patients elsewhere, either to county hospitals—where they often sat for hours on wooden benches waiting to be called—or historically black institutions. The black institutions were a far cry from whites-only hospitals, Smith says. "They were put together with "scotch tape and bailing wire."

Black patients could sometimes get care at medical schools and teaching hospitals by serving as "teaching material"—a dehumanizing term used to describe black patients who allowed medical students to hone their skills by treating their illnesses, says Smith, whose book on the impact of Medicare on Civil Rights, "Power to Heal," will be published by Vanderbilt Press next year to commemorate the 50 th anniversary of Medicare's implementation.

With the passage of Medicare, hospitals quickly integrated—a thousand in less than four months, Smith says.

Progress was swift because of the way the program was set up. The Johnson administration's Office of Equal Health Opportunity—a tiny office, with just five employees buried beneath layers of bureaucracy in the Department of Health, Education and Welfare—was charged with certifying hospitals to get federal funding based on whether they discriminated or not.

HEW Secretary John Gardner, recognizing the enormity of the task, decided to call in as much staff as necessary to enforce the law, Smith says.

Not wanting to attract attention, he put out a quiet call for volunteers. More than 1,000 people from federal agencies offered their help, along with tens of thousands of Civil Rights organizers. Field inspectors fanned out to hospitals to make sure they were in compliance with the law and eligible for federal funds.

"They wouldn't let anybody off the hook," Smith says. "The reason they were so successful is that they had this secret army of local civil rights workers and local health workers making sure [the hospitals] complied. Hospitals quickly figured out that they couldn't fake it."

The Johnson administration was determined that the transition would proceed smoothly—and was ready to call out the National Guard or the military if any hospitals barred their doors to patients or if mobs formed in protest.

"I went to the White House the week before the program began, and I was told, 'Goddammit, there aren't going to be any screw-ups,' " Marmor says. "There were helicopters, National Guard, God knows what else, all directed toward avoiding any symbolic catastrophe."