In the spring of 1868, the hottest ticket in Washington was the one to attend Andrew Johnson’s impeachment trial.

The desirability of obtaining such a ticket was understandable. This was, after all, the first impeachment of a president.

“Aside from being one of the most dramatic events in Senate history, the trial was the focus of the city’s social season,” the U.S. Senate itself says.

Also, one had to assume there would be no live-tweeting.

Interest in the trial was so great that police officers were ordered to the Capitol’s doors to hold back the unruly crowds. The Senate, faced with a security problem and a unique opportunity to devise a system pitting the haves against the have-nots, came up with a ticket policy for the proceedings.

Each day, 1,000 tickets were printed. The colors changed every day. What didn’t was the allotment.

The diplomatic corps: 40.

The president: 20.

Each senator: 4.

Chief Justice Salmon P. Chase: 4.

Each representative: 2.

This system created a gallery that was not exactly of the people. Ticket grantees tended to give their allotted tickets to — you guessed it — family members, high-society figures and political supporters. African Americans were not allowed.

“With opera glasses, the women and men in the galleries peered at the scene below,” wrote Brenda Wineapple in her recent book, “The Impeachers: The Trial of Andrew Johnson and the Dream of a Just Nation.”

That first day, Chase’s daughter, Kate Chase Sprague, showed up in “fawn-colored silk, Etruscan earrings, and bangles of frosted gold,” Wineapple wrote.

Confederate spy Belle Boyd attended. So did renowned sculptors, friends of journalists, businessmen — basically the crowd you’d expect to see today at the White House holiday party.

These days, the tickets are collector’s items, occasionally showing up on eBay and in gallery auctions for more than $1,000.

“Unused, with stub. Slight wear on side where stub and ticket were attached. Rare to find both ticket and stub, dark blue color ticket,” one listing says. “Will consider offers.”

As for the current impeachment, ticket demand doesn’t seem nearly as frenetic as it was in 1868. Senate gallery passes are available from constituents’ individual senators.

Meanwhile, searching for impeachment tickets on StubHub generated this automated response: “There aren’t any events on the horizon right now.”

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