The Senate majority leader first floated providing a pro-rated piece of wall money for President Donald Trump, which Schumer rejected. Then the minority leader tried to isolate the troubled Department of Homeland Security spending bill and fund the rest of the government, which McConnell spurned.

Finally, they hit upon a solution.

“I said, ‘Here’s my proposal to you. Let’s do a conference committee. They are good at it, they get along, they’ve done the other six budget bills, they can do this,’” Schumer recounted in his office Thursday as a months-long funding crisis was concluding. “And he accepted. And I think that paved the way to getting this done.”

When Trump first announced he was giving Congress three weeks to reach a border security deal, few in Washington thought bipartisan negotiations would achieve anything.

But the story of how the conference committee and its leaders succeeded after so many brutal months fighting over Trump’s wall is a simple one, according to more than a dozen lawmakers and aides: Trump largely stayed out of it. And seasoned veterans were allowed to do what they’ve done their entire congressional careers — figure out diplomatic ways to spend hundreds of billions of dollars.

“He gave them the space to do what they wanted to do,” said Sen. Lindsey Graham (R-S.C.), a close Trump ally. And nothing could get done until negotiators got “Pelosi and Trump and Schumer out of the room,” added Rep. Mike Simpson (R-Idaho).

The negotiations broke down over the weekend, but senior lawmakers didn’t really sweat until Trump was presented with the final product. In true Trump fashion, the president kept everyone waiting to know whether he’d cast the city into chaos once again. And then he stunned even members of his own party by deciding at the eleventh hour to pursue an explosive national emergency declaration to further fund his wall.

The week leading up to Friday’s government funding deadline was characterized by a dramatic round of ups and downs.

On Monday, when Senate Appropriations Chairman Richard Shelby (R-Ala.) announced that a deal had been reached, most of Congress was ecstatic and relieved the impasse that led to the longest shutdown in history would finally be ending.

But with no bill text, Trump was perplexed.

As Shelby walked the president through the agreement on Tuesday, the president began venting about the legislation. Trump was not happy to learn the bill would leave him with about a quarter of the border barrier funding he’d insisted upon in the run-up to the shutdown.

The president’s initial anger at what the conference committee produced brought Democratic delight. Over and over, the president had tried unsuccessfully to peel off moderate Democrats to break with Schumer and Speaker Nancy Pelosi and force the party to cave on wall funding.

“He’s not a great negotiator. He’s a bully. And that’s what the real estate people will tell you in New York. He doesn’t come up with clever compromises, he tries to bully them, sue them,” Schumer said. “He knows he can’t push me around.”

Negotiators wouldn’t iron out the final details and unveil the measure until late Wednesday night — further worrying the White House about what exactly was in the bill. Congressional sources described an intense 24 hours of conversations with the president. With no bill text, opponents of the deal began attacking it and concern grew that Trump wouldn’t support it.

The president and acting chief of staff Mick Mulvaney began dialing McConnell and House Minority Leader McCarthy (R-Calif.), nervous about certain provisions. The president never threatened to veto the package, but was concerned that it would limit his ability to build the wall.

The GOP leaders pressed home their main points to the president repeatedly: Democrats agreed to $1.375 billion in new barrier funding that Trump could call a wall, and Republicans rejected a statutory cap for ICE detention beds that Democrats sought.

“Nancy Pelosi said not one dollar for the wall, said she would end all the detention beds, and they’d eliminate ICE,” McCarthy argued in an interview. “The president came out well on this bill.”

While Trump told Shelby he was on unhappy on Tuesday, by Wednesday evening he was feeling better.

“He seemed to be very interested. I don’t recall him saying he was unhappy,” Shelby recounted.

In fact, at one point on Thursday, just hours before Congress was set to vote, Mulvaney suggested passing a stopgap spending bill to allow a waffling Trump more time to review the package without tumbling into another shutdown. That’s something most on Capitol Hill loathed: The longer a bill hangs out there, the more likely it is to accrue opposition. And a stopgap measure actually would give Trump less money for his restrictive immigration priorities.

Mulvaney’s idea would also have scuttled months of hard work on what may be the last substantial spending agreement before the 2020 election to be crafted by Shelby, House Appropriations Committee Chairwoman Nita Lowey (D-N.Y.) and the other top two spending chiefs, Sen. Patrick Leahy (D-Vt.) and Rep. Kay Granger (R-Texas).

The foursome had already brought the agreement back from the brink of collapse over the weekend after a surprising issue almost derailed the talks: A proposal by liberal Democrats to place a hard cap on the number of undocumented immigrants that Immigration and Customs Enforcement could hold in the interior of the country.

Democrats maintain they had been negotiating with Republicans on capping detention beds all along, but Republicans insist the idea came out of nowhere over the weekend. It was a flashpoint that threatened to tank the talks, but it also seemed to earn Democrats new leverage over the GOP on fence funding.

“I think that cost a half a billion dollars for us,” said a GOP source involved in the talks.

Shelby initially walked away from the negotiations on Saturday over the detention beds dispute: “I said ‘no way,’ because it was ridiculous,” he said. He then went on TV Sunday and claimed everything was slipping away.

House Democratic negotiators held an emergency conference call Sunday morning as Shelby was diminishing the chances of a deal. Pelosi, who had been keeping in close touch with Schumer and negotiators over the weekend, dialed in from the West Coast to get a read on the standoff.

Lowey and Shelby then talked on the phone several times, and Lowey suggested the four old bulls meet.

Pelosi phoned Lowey and California Rep. Lucille Roybal-Allard, another top Democratic negotiator, on Monday afternoon on her way to the airport, and suggested the Democrats’ position on detention beds was untenable.

Later Monday afternoon the top negotiators — Lowey, Shelby, Leahy and Granger — met in Shelby’s office for more than an hour. In the meeting, Democrats expressed flexibility on the detention beds issue, then pressed pause as senators left for a vote.

Meanwhile, House Democratic staffers were busy preparing a stop-gap funding bill they could file as soon as Monday night if the last-ditch effort went nowhere.

“We thought the talks had completely blown up,” said one Democratic source familiar with the negotiations.

They spending chiefs reconvened in Leahy’s office, then broke for a House vote. Lowey and Roybal-Allard met with the other House Democratic negotiators one last time. The group agreed to relent on the cap on detention beds in exchange for less barrier money.

Lowey, Shelby, Leahy and Granger then met once more at 8 p.m., before announcing the pact. The four wrangled over the number of detention beds to fund in the bill, then moved on to barrier spending.

The group had been discussing $1.45 billion in funding for barriers, but Lowey said she couldn’t go back to her caucus unless that number was reduced to $1.375 billion.

Finally, they had a deal. Leahy and Shelby stood side by side in front of a crowd of reporters announcing an “agreement in principle” had been reached, in a bipartisan show of support.

“I don’t love everything in this bill. I’m sure that Republicans don’t love everything in this bill,” Lowey said Thursday night. “But we understand — Democrats and Republicans — that we have a responsibility to fund the government and move on.”

Yet the talks again got a dicey on Tuesday as congressional staff haggled over language that would protect a handful of specific “sensitive areas” along the border — including a butterfly nature preserve — from barrier construction. The language was a top priority for Rep. Henry Cuellar (D-Texas), the only conferee from the border.

In the final hours before the bill was set, Democratic and Republican leaders fought over multiple other provisions — everything from an extension of the Violence Against Women Act to back pay for federal contractors. In the end, all extraneous elements were left out of the final package.

Democrats also sought limits on reprogramming ICE funds and changes to asylum rules, but Republican negotiators again refused, said the sources.

Within 24 hours after the text of the 1,159-page bill was released, the Senate had passed it 83-16 and the House had followed suit, 300-128. The president would sign it into law on Friday in the Rose Garden.

Yet even as Trump tried to calm anger on the right by simultaneously endorsing the package and declaring plans to declare a national emergency through an unusual floor announcement from McConnell, Schumer kicked back in his office feeling like he’d won the only battle that mattered.

Regardless of how Trump’s gambit plays in the courts, he didn’t get what he wanted from Congress.

“No wall. That’s the watch word. The whole debate here was whether he was going to get his wall,” Schumer said. “And he didn’t, at all.”

Sarah Ferris and Caitlin Emma contributed to this report.