I'm thinking pre-Star Trek and post-Star Trek.
I find reading about historical events and cultures as described by the contemporaries illuminating. Winston Churchill's books on WWII and William T. Sherman's memoirs are interesting insights.
The multitude of biographies of Abraham Lincoln written over the last 140+ years give insight not only into this president, but also his biographers.
I think people in the future might look back on our time and say, "They thought and did that?" "Why were they so foolish then, Mommy?"