Not in your front yard: Why 'For Sale' signs are banned in Oak Park, Steven Jackson, Oak Park, April 2, 2019, available here
Back in 1960s and '70s, Chicago was going through a period of racial change. For years, African-Americans had been leaving their segregated Chicago neighborhoods and moving to other parts of the city. This shift in neighborhood demographics led to a lot of social unrest — sometimes violent — and a huge, slow-rolling wave of white flight. (This handy little GIF sums it up pretty well.)
The process of racial change was helped along by the real estate practice of blockbusting. If you're not familiar with this nasty little gerund, it worked like this: Real estate agents would knock on doors and suggest that African Americans were moving in and property values were sure to plummet. They'd hire black actors to walk down the street, or push baby strollers on the sidewalk. And they'd post plenty of real estate signs, so there'd be no mistaking that the neighborhood was about to flip from white to black.
Once the white homeowners were good and scared, the real estate agents bought those houses for a song, and sold them to African-Americans for a profit.
"It was going on a block by block basis, and a lot of fear and a lot of panic was generated," recalls Roberta Raymond, a sociologist, housing activist, and the founder of the Oak Park Regional Housing Center. She was born and raised in Oak Park, and is often credited with spearheading integration and fair housing in the village.