Dr. Martin Luther King Jr. was bringing the civil rights movement to the cities of the North. In January 1966 he’d rented an apartment on the West Side of Chicago. On this date 45 years ago, he met a violent reaction in his adopted city.

King was leading a series of protest marches against housing segregation. Chicago’s white realtors often refused to show homes in white neighborhoods to African-Americans. This was a particular problem in the Marquette Park neighborhood, scene of that day’s march.

The protesters planned to demonstrate at three realty offices along 63rd Street. Opponents of open housing were determined to demonstrate against the demonstrators. The police were deployed to keep the two groups separate and peaceful.

A few open housing advocates arrived on the scene early, and marched without serious incident. The thousand or so opponents stood on the sidewalk behind the police lines. They jeered and yelled insults, but did nothing more. Then the main body of 700 marchers drove up in a motorcade.

King’s car pulled to the curb at 63rd and Sacramento. As he got out, a rock sailed through the air and hit him in the back of the neck. He fell to one knee. After a few seconds he got up, and prepared to lead his people.

“I have to do this—to expose myself—to bring this hate into the open,” King told them. “I have seen many demonstrations in the South, but I have never seen anything so hostile and so hateful as I’ve seen here today.”

The march began. Now the crowd behind the police lines hurled rocks, bottles, firecrackers, chunks of concrete, and anything else within reach. Someone threw a knife. From time to time, the people on the sidewak tried to push through to get at the marchers. The cops held firm.

The day ended with 30 people injured, including King and four policemen. Forty-one persons had been arrested, mostly whites who’d tried to block off Kedzie Avenue.

Later in the year an agreement was reached between the open housing advocates and the Chicago Real Estate Board. The first, faltering steps had been taken toward ending segregated housing in the city.