This article has been updated with additional endorsements (and two anti-endorsements).

The Arizona Republic was very well aware of the tradition it was breaking by endorsing Hillary Clinton on Tuesday evening. It teased the upcoming endorsement Monday, creating a video highlighting that it had never, in its history, endorsed a Democrat. That was the lead of the endorsement itself: "Since The Arizona Republic began publication in 1890, we have never endorsed a Democrat over a Republican for president. Never." Got it.

As my colleague Cal Borchers noted earlier today, the Republic is not alone. A number of other major newspapers have broken with long-standing tradition to either back Clinton or not endorse Donald Trump. Newspapers were slow to transition to the digital world (as you may have heard), so it's a bit tricky to find their, say, 1944 endorsements online. (The Cincinnati Enquirer staff note that they'd backed Republicans going back a century "as best we can tell.") Here's what we found; if you have additions, let us know.

There are some interesting exceptions. In 1968, the Republic couldn't decide between Hubert Humphrey and Richard Nixon, so it didn't endorse anyone. In 1964, the Dallas Morning News was undecided between Lyndon B. Johnson and Barry Goldwater. Voters had much less difficulty, and Johnson won in a blowout.

The main trend worth noting is that 11 of the 16 newspapers listed here endorsed Mitt Romney in 2012; 10 of them backed John McCain in 2008. None are backing Trump this year. In nine cases, the newspapers had endorsed the Republican candidate going back to at least Richard Nixon.

Many of those papers noted that they were breaking with tradition, either in choice or in timing.

Houston Chronicle: "The Chronicle editorial page does not typically endorse early in an election cycle; we prefer waiting for the campaign to play out and for issues to emerge and be addressed. We make an exception in the 2016 presidential race, because the choice between Hillary Clinton and Donald Trump is not merely political. It is something much more basic than party preference."

Cincinnati Enquirer: "The Enquirer has supported Republicans for president for almost a century – a tradition this editorial board doesn’t take lightly. But this is not a traditional race, and these are not traditional times."

Dallas Morning News: "We don't come to this decision easily. This newspaper has not recommended a Democrat for the nation's highest office since before World War II — if you're counting, that's more than 75 years and nearly 20 elections."

Tulsa World: "Since 1940, the Tulsa World has consistently endorsed the Republican nominee for president, but we’re not willing to do that this time.

"Neither are we willing to endorse the Democratic candidate or any other candidate."

San Diego Union-Tribune: "This paper has not endorsed a Democrat for president in its 148-year history. But we endorse Clinton. She’s the safe choice for the U.S. and for the world, for Democrats and Republicans alike."

USA Today: "In the 34-year history of USA TODAY, the Editorial Board has never taken sides in the presidential race. ... We’ve never seen reason to alter our approach. Until now."

Deseret News: "For 80 years, the Deseret News has not entered into the troubled waters of presidential endorsement. We are neutral on matters of partisan politics. We do, however, feel a duty to speak clearly on issues that affect the well-being and morals of the nation. Accordingly, today we call on Donald Trump to step down from his pursuit of the American presidency."

And, of course, the Arizona Republic: "The 2016 Republican candidate is not conservative and he is not qualified.

"That’s why, for the first time in our history, The Arizona Republic will support a Democrat for president."

Weirdly, this all fits squarely into Trump's campaign argument: The establishment and the media are out to get me. It's a bulletproof response to any criticism from any individual or entity. Sure, newspapers that have for decades unquestioningly endorsed Republicans have given Trump a pass. That just shows how they are part of the rigged system, or something.

Trump did get the endorsement of the New York Observer. It is owned by his daughter Ivanka's husband, Jared Kushner.