At a very young age I learned about sundown towns. It was mixed in with all those other lessons that only black kids used to get. Those lessons and warnings handed down by our elders on how to conduct ourselves in an integrated society that discriminated and held double standards.

In one of those lessons, my folks told me about a sign that once stood just outside of a small town in the area. In crude hand-painted letters was a warning that blacks should not let the sun set on them in this town. Close to it stood another sign that said “Welcome.”

If you were black you didn’t have to guess which sign was meant for you.

Years later, as a young man working for the highway department in this town I remembered that story. The sign had long since been taken down but still no blacks lived in the town. Perhaps that was the result too, of lessons from somebody else’s elders not forgotten.

But neither set of lessons were ever written down. That’s why the story of sundown towns is an undocumented history. But James Loewen, a Washington, D.C., author, explores this unwritten history of discrimination in a new book called, “Sundown Towns: A Hidden Dimension of American Racism.”

In the book and a History Channel Magazine article, Loewen describes sundown towns as those places across America that drove out black populations or forbade them to live within their city limits or be in them after dark.

What’s surprising is the fact that these unwritten sundown ordinances don’t date back to the Civil War. According to the book, there was a period between 1863 and 1890 when blacks could live anywhere in America. Some communities, largely Quaker and Republican populations, actually even welcomed black residents.

But something happened between 1890 and 1940. Already tenuous race relations turned for the worse. There were more lynchings and race riots. Many towns began ordering blacks to move out. Any black caught in these towns after the sun went down found hell to pay. And it didn’t just happen in the southern states.

According to Loewen’s research, Illinois, Utah and Nebraska and other northern states had these sundown ordinances. In fact, more than 10,000 towns across the country had unofficial sundown policies even as late as the 1970s. Many of them even tried to make it an official law.

Blacks traveling the country during the heyday of sundown towns relied on word of mouth and race specific travel booklets like the “Travelguide: Vacation and Recreation Without Humiliation” and the “Negro Motorist Green Book” that pointed out which towns to avoid. The books also listed those hotels and restaurants that were hospitable to black clientele. Loewen said that even today, there are some communities that still use subtle measures to keep black residents out. They may appear “accidentally” white, but use real estate and rental denials and other tactics to remain minority free. Mexican-Americans are experiencing this type of discrimination now.

But today we also have some good friends who live in that small community that once had the sign. And no one can convince me that this couple have a racist bone in their bodies. Their biracial grandchildren visit often.

You can’t judge all by the actions of some, no matter what the signs say.

Alonzo Weston can be reached

at alonzow@npgco.com.