The political dynamics of the Republican Party’s so-called Wisconsin Mafia have been fascinating to watch this year, but never more so than this week.

RNC Chairman Reince Priebus’ anger at Donald Trump over his failure to endorse House Speaker Paul Ryan, who is being challenged in next week Republican primary by businessman Paul Nehlen, has to be understood in the context of the chairman’s relationship with Ryan.

Priebus and Ryan are both from the Badger State, and are friends. They also both have deep connections with Wisconsin Gov. Scott Walker.

And while Priebus has become one of Republican nominee Donald Trump’s biggest boosters over the past several months, Ryan and Walker have been reluctant supporters, at best.

Ryan, before and after endorsing Trump a month ago, has repeatedly denounced Trump’s most controversial statements. Walker, who dropped out of the presidential race early, waffled on endorsing Trump before eventually doing so, and in the weeks leading up to the Republican convention was said by multiple sources to be exploring whether it was possible for him to emerge at the convention as an alternative to Trump.

Priebus played a crucial role in getting Ryan to overcome his reservations about Trump. When Ryan said in May, after Trump unofficially clinched the nomination, that he couldn’t yet support Trump, Trump called Priebus within minutes of seeing Ryan’s comments on CNN. Priebus then called Ryan, he later told Politico, and he shuttled back and forth on the phone between Ryan and Trump to arrange a meeting between the two a week later at the RNC headquarters on Capitol Hill.

Many observers believe that Priebus leaned heavily on Ryan and pleaded with him to endorse Trump, for the sake of the party and as a personal favor. Hence, Trump’s refusal now to endorse Ryan’s reelection in the Republican primary next week would be seen by Priebus as a personal betrayal.

Trump not only refused to endorse Ryan when asked by a Washington Post reporter Tuesday. He also threw Ryan’s own words from May back at the speaker. “I’m not quite there yet,” Trump said. (Trump running mate Mike Pence is apparently there, announcing his support of Ryan on Wednesday.)

House Speaker Paul Ryan and Reince Priebus, chairman of the Republican National Committee, at the Republican National Convention in Cleveland, July 19, 2016. (Photo: J. Scott Applewhite/AP)

“For Trump to say that … was also kind of a personal shot at Reince, or at least he would take it as personally,” said one former high-ranking RNC official.

A current top RNC official told Yahoo News there was an element of truth to this.

“Part of his mindset is, ‘Wait a second, dude. You’re now in my backyard. I care about Wisconsin and Paul. I don’t see how this helps,’” the RNC official said. Priebus does feel he “went to bat” for Trump with Ryan.

But the RNC official also said that Priebus’ relationship with Ryan was only part of the reason for the RNC chairman’s anger at Trump.

“It’s a culmination of a lot of things. One, we’re trying to clean up the Khan stuff. So it’s like, ‘You’ve got to be kidding me,” the RNC official said. “No. 2, Hillary is getting crushed on lying, and we’re having a conversation about this? There’s eight things happening at once.”

“It’s less about Paul and more about, I’m out there every day talking about how we need to keep the team together, and then you go out and do this?” the RNC official said.

Charlie Sykes, a conservative Wisconsin radio talk show host who has been an outspoken critic of Trump, told Yahoo News: “Reince is a friend, but I think is a tragic figure here.”

“He’s the guy who brokered, obviously, the deal with Ryan and with Walker,” Sykes said, referring to Ryan and Walker’s endorsements of Trump.

“So you can’t overstate the humiliation, the personal and political humiliation for Reince Priebus, when Trump does this with Ryan,” Sykes said. “This means so much to Reince. This is above politics. It’s very personal that he wanted to unite the party, get Ryan and Trump on the same page, get Walker.”

“He’s basically mortgaged his entire reputation and career for Donald Trump,” Sykes said of Priebus.

Trump will campaign in Green Bay, Wis., on Friday, and while Congress is out of session, Ryan will not appear at the rally with Trump. Neither will the state’s Republican senator, Ron Johnson, or Walker.

“I’m 100 percent with Paul Ryan,” Walker said Wednesday.