Washington(CNN) The State Department released the very last of Hillary Clinton's work-related emails Monday, capping off a nearly year-long process that began when The New York Times revealed that Clinton had been exclusively using a private server to conduct official business as secretary of state.
For the State Department, the Clinton campaign and journalists covering the story, the releases have been at various times tedious, contentious, frustrating, revealing and opaque.
Here's what we've learned so far, and what remains unanswered.
Monday's final release marks the end of a major effort by the State Department's Freedom of Information Act office, which had to review more than 52,000 pages of the former secretary of state's emails in the past year before releasing them to the public.
Clinton called for the emails to be released when news of her unusual communications set-up was first revealed. The State Department was then ordered to provide them to the public on a rolling basis by a federal judge in a FOIA lawsuit.
But it would be premature for those staffers to celebrate, since the department is still in the midst of processing dozens of related requests.
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The State Department is furthermore being sued for the emails of top aides, and for the tens of thousands of emails Clinton deemed personal and didn't turn over for review.
At a hearing last week in one such lawsuit, U.S. District Judge Emmet Sullivan said he's considering asking the State Department to subpoena Clinton, and aide Huma Abedin, in an effort to learn more about those emails.
And Clinton's emails continue to get scrutiny beyond the State Department. On Monday, State Department Spokesman John Kirby told reporters one email is being withheld from the public in full at the request of law enforcement.
Kirby would not comment on the content of the email, but he emphasized it is not classified.
Clinton's server is also the subject of an FBI investigation, which has allowed her Republican opponents on the presidential campaign trail to raise the specter of possible indictment.
In an interview Monday with Fox News, Attorney General Loretta Lynch said the investigation is "being handled like any other review that we do into how any agency has handled classified information," but she had no updates on the time frame for its completion.
"What's most important is to follow the facts, follow the law, and come to an independent conclusion as to what may or may not have happened," she said.
Much of the conversation surrounding Clinton's use of a private server for State Department business has revolved around the question of whether she took adequate measures to safeguard sensitive information.
Clinton and her aides insist none of the emails she sent or received were marked as classified at the time they were sent, but more than 2,101 have been retroactively classified during the State Department-ledpre-release review process.
This includes 22 emails upgraded to Top Secret -- the highest level -- and withheld by the State Department in full.
Those emails in particular are the subject of intense scrutiny, sometimes leaving the State Department and intelligence community at odds.
Last month, a leaked letter from intelligence community Inspector General I. Charles McCullough III revealed the existence of "several dozen" cases of classified information originating from intelligence agencies, some of which, they said, should have been considered classified during Clinton's tenure.
Those documents included information on so-called "Special Access Programs," a highly sensitive subset of information off limits even to most Top Secret clearance holders.
Clinton's campaign has waded into the fray, suggesting the upgrades and intelligence agency disparities are the result of "over-classification run amok." Clinton campaign spokesman Brian Fallon has also blamed political operatives in the inspector general's office and on Capitol Hill for leaking information about the normally secretive review process.
Little is known about the content of the most sensitive emails beyond what's been outlined in McCullough's letter, but Democratic California Sen. Dianne Feinstein, a member of the Senate intelligence committee who has seen the now-Top Secret communications, recently said in a statement that "none of those email chains originated with Secretary Clinton."
"It has never made sense to me that Secretary Clinton can be held responsible for email exchanges that originated with someone else," she added.
As a sign that the inter-agency debate continued until the very last days of the review, State Department Spokesman John Kirby told reporters Monday that one email flagged by the intelligence community as potentially containing Top Secret information was deemed not to have and will be released Monday with limited redactions and upgrades.
That email, released in in Monday's batch, involved information about a conference call on North Korea, convened after the country conducted a missile test in July 2009. The now-classified information was sent by a career diplomat and forwarded to Clinton by Abedin.
The ongoing debate over classification has led the State Department to announce a separate review, led by the Bureaus of Diplomatic Security and Intelligence and Research, into whether any of the information retroactively upgraded should have been marked as classified when sent.
Cabinet posts are theoretically outside of the political sphere, but Clinton was kept keenly aware of the political climate throughout her tenure.
Aides often forwarded Clinton information on her favorability ratings, even as she told the public she was undecided on making another run for the White House.
In March 2009. Mills forwarded her a CNN poll showing "Clinton has high job approval."
Reines sent her a similar poll two years later, adding, "This is why we cooperate with so many profiles - and just wait until 19 million Americans to read PEOPLE next week."
Blumenthal frequently offered his thoughts on politics, writing enthusiastically in 2010, "can you call me now? eureka idea for midterms!! want to run by you, think it can work."
Clinton's core staff at the State Department was both loyal and adoring, as evidenced by the dozens of praise emails she received on a regular basis.
Aides frequently forwarded positive articles about Clinton, including a Drudge Report piece titled "Clinton Popularity Prompts Buyer's Remorse."
When a photo of Clinton on her Blackberry turned into a viral Internet meme, Cheryl Mills wrote simply, "You look cute."
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And the praise didn't just come from her staff.
On January 23, 2013, after Clinton testified before the Senate Foreign Relations Committee on the Benghazi consulate attack, top White House economic adviser Gene Sperling wrote to Mills that Clinton "was a great combo of patient, emotional and fighting-back tough. Made me proud." That email was forwarded to Clinton.
Another Obama administration official, Liz Sherwood-Randall, wrote to Sullivan: "If you get a chance — please tell HRC that she was a ROCK STAR yesterday. Everything about her 'performance' was what makes her unique, beloved, and destined for even more greatness."
"She sets a standard that lesser mortals can only dream of emulating," Sherwood-Randall added.
Among the emails retroactively classified at the lower tiers of Confidential and Secret are communications between top State Department officials, foreign dignitaries and advisers outside of the U.S. government, who weighed in on a number of policy discussions.
Many of those emails were not sent to Clinton directly but rather were forwarded to her by key aides, including Chief of Staff Cheryl Mills, Deputy Chief of Staff Huma Abedin and Jake Sullivan, who served as both director of policy planning and deputy chief of staff.
Abedin and Sullivan currently hold top positions on Clinton's presidential campaign.
Clinton's core team at the State Department was, in some ways, insular.
Senior officials who didn't know her email address often emailed Abedin, Mills or Sullivan when they needed to convey messages to the secretary, showing how access to her was carefully managed.
In a July 2012 email forwarded to Clinton, staffer Philippe Reines humorously alluded to the closed nature of the former secretary's inner circle by creating a flow chart to determine who would ride with her on the road.
The chart asked a series of yes or no questions starting with, "Huma there?," and ending with scenarios in which Reines himself might be allowed to join in the vehicle.
Aside from her inner circle, Clinton also received emails from some of her department's top officials, including now-classified emails from then-Deputy Secretary William Burns and former Under Secretary of State for Political Affairs Wendy Sherman.
She also heard regularly from Tony Blair, the former British prime minister who served as a Middle East peace envoy for the United Nations at the time, and on occasion from Ashraf Ghani, a prominent Afghani politician who has since become president of that country.
Clinton also received emails from her eventual successor at the State Department, John Kerry, who chaired the Senate Foreign Relations Committee during her years in office and himself sometimes emailed from a personal email account.
Not immune from the controversy, several emails sent by Kerry have now been upgraded to classified, including a few in Monday's batch.
Perhaps the most controversial member of her kitchen cabinet was Sidney Blumenthal, a friend and confidant who sent her hundreds of emails on both policy and politics, even though he was blocked by the Obama administration from joining her official team at the State Department.
Critics have wondered why Blumenthal had such direct access to, and perhaps influence over, Clinton, when many officials in her own department didn't have her personal email address.
Clinton has dismissed the extent of Blumenthal's influence, calling the emails "unsolicited," even as she thanked him repeatedly at the time for offering his perspective.
"I'm going to keep talking to my old friends, whoever they are," Clinton said during a May press conference in Iowa. "He's been a friend of mine for a long time. He sent me unsolicited emails, which I passed on in some instances, and that's just part of the give-and-take."
Unsurprisingly, Clinton emailed family members as well. And it was an email to daughter Chelsea Clinton on the night of the attack on the U.S. consulate in Benghazi that brought Clinton pointed questions when she testified before the House Select Committee on Benghazi in November, as some lawmakers wondered why she attributed the attack to "an Al Queda-like group" in the email while publicly suggesting protesters played a role.
Despite her unusual decision to set up a private email server at her home, Clinton's communications often display a lack of savvy when it comes to technology.
In a June 2010 email to Reines, Clinton is excited to learn that her new iPad (called the "hPad" by her loyal staffers) has arrived, and asks, "do you think you can teach me to use it on the flight to Kyev next week."
And even as she elected not to use a state.gov account, Clinton expressed surprise when other staffers did the same.
At one point in 2011, Sullivan passed along insights from a State Department employee using a personal account, prompting Clinton to ask, "Who does he work for now?"
When Sullivan said the man worked for the State Department, Clinton responded, "I was surprised that he used personal email account if he is at State."
Other emails reflect Clinton's frustration with the State Departments communications systems, and the limits presented by the very systems meant to protect classified information.
In one such email, Sullivan tells Clinton a statement by Blair was put on the classified system "for reasons that elude me," prompting Clinton to reply: "It's a public statement! Just email it."
"Trust me, I share your exasperation," Sullivan replied. "But until ops converts it to the unclassified email system, there is no physical way for me to email it. I can't even access it."
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On a separate occasion, Clinton and Sullivan exchange emails on a set of "tps" -- presumably talking points, which he's trying to send to her on a secure fax line.
"If they can't," Clinton replies, "turn into nonpaper w no identifying heading and send nonsecure."
There's no indication whether the talking point were classified, but the exchange led to criticism from Republican Iowa Sen. Chuck Grassley, a frequent Clinton critic, who called the chain "disturbing" and asked the former secretary to "come clean."
Additional emails, on which Clinton was not copied, also shed light on how her email set-up was viewed at the State Department.
A set of emails released to the website The Daily Caller last month, for instance, show that some officials suggested providing Clinton with a State Department Blackberry, which Huma Abedin resisted.
"Let's discuss the state blackberry, doesn't make a whole lot of sense," she replied.
There were also discussions about setting up a "stand-alone PC" for Clinton that would allow her to access her personal emails at the State Department.
In an email exchange later obtained by the conservative legal watchdog group Judicial Watch, Under Secretary for Management Patrick Kennedy tells Mills the computer "is a great idea."
Ultimately, State Department officials say the computer was not set up. It's unclear why the idea was ultimately nixed, but it might relate to Clinton's lack of computer knowledge, as relayed in a later email.
"I talked to Cheryl about this," Lewis Lukens, then a deputy assistant secretary of state, writes. "She says a problem is hrc does not know how to use a computer to do email -- only [Blackberry]. But, I said would not take much training to get her up to speed."