On a bright, cold morning last November, I walked Boston’s Black Heritage Trail, a hidden gem among the city’s trove of historic sites. I had followed it decades ago as a graduate student and was returning now with my mother after a recent move to Massachusetts. I was especially looking forward to revisiting one stop on the trail — Lewis Hayden’s house, in the now-affluent Beacon Hill neighborhood.

Hayden’s story had made a strong impression on me. His immediate family was shattered by slavery. He had escaped from Lexington, Ky., not far from where I grew up in Ohio, and went on to build a remarkable life in Boston. Years after my first visit to the house, which was a stop on the Underground Railroad, I could still picture the green window shutters and elegant doorway. I associated Lewis Hayden with the place where I grew up, with family, perseverance and good will. So I was disconcerted by what I found when I arrived at the house that autumn day.

The ruddy bricks, green shutters and white curtains were just as I remembered them. But here was something new — a red, white and blue sticker on the windowpane trumpeting the National Rifle Association. This moment, which might not have caused a reaction in others, set me on a path of reflection, not just on the life of Hayden and those like him, but on the meanings of African-American gun ownership and my own deeply held beliefs about guns. What I learned surprised me.

My response to seeing the sticker was strong. I am an African-American historian and, on the matter of guns and most other political issues, decidedly liberal. To me, the pairing of Lewis Hayden and the N.R.A. felt like an affront. I knew for certain that Hayden fought for the right to be free from violent repression by white citizens wielding the weapons of guns, capital and political influence. I knew that he lost his family through a cruel, extractive system that reinforced — in fact, depended on — the ability of whites to inflict violence on the bodies of black people without legal repercussion.