WASHINGTON - It’s been a long, strange road for Rudy Giuliani, the hard-nosed prosecutor who gained fame as “America’s Mayor” for his leadership in New York City after the terror attacks on September 11, 2001.

Once seen as a promising Republican presidential candidate himself, Giuliani is now trying to beat back accusations that he was a key player in an international scandal that has President Donald Trump facing an impeachment inquiry.

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Over the course of the past two years, Giuliani, 75, has held multiple meetings with officials from Ukraine as part of an effort to persuade that country’s government to open an investigation focused on former Vice President Joe Biden and his son, Hunter Biden, who served on the board of a Ukrainian energy company called Burisma Holdings.

At the same time, Giuliani was pushing for a separate investigation into alleged cooperation between Ukrainian officials and Hillary Clinton’s campaign in the 2016 election, suggesting that Joe Biden had also played a role in that unproven conspiracy.

FILE - U.S. Vice President Joe Biden and former Secretary of State Hillary Clinton attend a ceremony to unveil a portrait honoring retiring Senate Minority Leader Harry Reid on Capitol Hill in Washington, Dec. 8, 2016.

Joe Biden, of course, has long been seen as Trump’s most likely Democratic opponent in the 2020 presidential election, and is the opponent that reportedly most concerns the president. Giuliani has taken these actions, he said, in his capacity as the president’s personal lawyer.

Whistleblower complaint

The story came to a head this week with the release of a whistleblower complaint, later confirmed by a rough transcript of the phone conversation released by the White House, that claimed Trump pressured Ukrainian President Volodymyr Zelenskiy to investigate the Bidens in the context of a phone call about military aid.

But Trump’s July 25 phone call with Zelenskiy only took place after Giuliani did months of groundwork, jetting across the Atlantic to meet with an assortment of current and former Ukrainian officials to press his theories about the Bidens.

FILE - Ukrainian President Volodymyr Zelenskiy speaks during a meeting with law enforcement officers in Kyiv, Ukraine, July 23, 2019.

In fact, the whistleblower complaint also accused Giuliani of complicating U.S. diplomatic efforts in Ukraine and forcing career State Department employees to attempt to “contain the damage.”

Speaking to The Washington Post earlier this year, Giuliani estimated that he had met with at least five current and former Ukrainian prosecutors in pressing his case against the Bidens.

He was also not shy about sharing his ideas publicly.

In May, for example, he demanded on Twitter, “Explain to me why Biden shouldn’t be investigated if his son got millions from a Russian loving crooked Ukrainian oligarch while He was VP and point man for Ukraine.”

In June, he again tweeted about Biden, suggesting that there were allegations that the vice president had “bribed” former Ukrainian Prime Minister Petro Poroshenko, though he did not include any evidence of such allegations, and none has since surfaced.

Diplomatic freelancing

Then-General Prosecutor of Ukraine Viktor Shokin speaks during news conference in Kyiv, Ukraine, Feb. 16, 2015.

Specifically, Giuliani has been pushing the theory that Biden, as vice president, took improper actions in 2015 by pressing the government in Kyiv to fire Prosecutor General Viktor Shokin, who was considered corrupt by a wide array of the United States’ European allies.

Giuliani’s claim, propounded in tweets, on television and in interviews, is that Joe Biden’s real motive was to quash an ongoing investigation of Burisma in order to benefit his son, who had been named a member of the company’s board, with a reported salary of $50,000 per month.

To date, Giuliani has produced no evidence that either of the Bidens took improper action. In fact, Ukrainian officials have said that at the time of the prosecutor’s firing, there was no investigation of Burisma for Biden to derail. Officials have also said they have no reason to believe Hunter Biden did anything illegal.

Despite criticism that he is operating as a shadow State Department, Giuliani has been defiant, even while admitting that he is interfering in the Ukrainian government’s affairs on the president’s behalf.

In an interview with The New York Times in May, he said, “We’re not meddling in an election; we’re meddling in an investigation, which we have a right to do.”

He added: “This isn’t foreign policy. I’m asking them to do an investigation that they’re doing already and that other people are telling them to stop. And I’m going to give them reasons why they shouldn’t stop it, because that information will be very, very helpful to my client, and may turn out to be helpful to my government.”

Giuliani’s freelancing in Ukraine drew the attention of members of Congress, who on September 9 complained in a statement to Secretary of State Mike Pompeo that “a growing public record indicates that, for nearly two years, the President and his personal attorney, Rudy Giuliani, appear to have acted outside legitimate law enforcement and diplomatic channels to coerce the Ukrainian government into pursuing two politically motivated investigations under the guise of anti-corruption activity.”

That letter was sent before the whistleblower complaint outlining Trump’s call to Zelenskiy, which led to an announcement by House Speaker Nancy Pelosi that the Democrat-led body would pursue an impeachment investigation of the president.

U.S. Secretary of State Mike Pompeo speaks during a press conference at the Palace Hotel on the sidelines of the 74th session of the U.N. General Assembly in New York, Sept. 26, 2019.

The chairmen of three House committees subpoenaed Pompeo on Friday over his failure to produce documents related to reported efforts by Trump and his associates “to improperly pressure the Ukrainian government to assist the President’s bid for re-election.”

Pompeo has not publicly discussed Giuliani’s dealings with Ukraine and the State Department.

Giuliani’s reaction to the whistleblower complaint has been fierce, with television appearances in which he claimed that he was actually acting at the behest of the State Department and reiterated his accusations against the Bidens.

In an interview with The Atlantic, during which the reporter described him as “very angry” and “shouting,” he said, “It is impossible that the whistleblower is a hero and I’m not. And I will be the hero! These morons — when this is over, I will be the hero.”

Long friendship

FILE - President-elect Donald Trump calls out to media as he and former New York Mayor Rudy Giuliani pose for photographs as Giuliani arrives at the Trump National Golf Club Bedminster clubhouse, Nov. 20, 2016, in Bedminster, N.J.

Trump and Giuliani have been friends at least as far back as 1989, when the developer supported Giuliani’s first bid for mayor of New York.

Giuliani, in turn, was one of Trump’s most ardent and aggressive supporters during the 2016 presidential election. His speeches and appearances were sometimes so over the top that pundits were openly questioning his sanity.

But Giuliani endeared himself to Trump, taking on some of the most unpleasant assignments as a campaign surrogate.

He was one of the only Trump surrogates willing to speak for the president in the days following the October 2016 release of the infamous Access Hollywood tape, in which then-candidate Trump was caught admitting to sexually assaulting women. Two days later, Giuliani appeared on all five major U.S. television Sunday talk shows.

Giuliani first came to broad public attention in the 1980s, while serving as U.S. Attorney for the Southern District of New York. He led multiple high-profile prosecutions of white-collar criminals and organized crime figures.

While he was praised by many for his record of successful convictions, he was also broadly criticized for heavy-handed tactics that resulted in the public humiliation of individuals who were never charged with wrongdoing.

Giuliani parlayed his tough-on-crime image into two terms as mayor of New York, during which time he focused on improving the quality of life in the city. He was known for pressing police to crack down on petty crime on the theory that doing so would also bring down levels of serious crime, and indeed, the city became considerably safer during his time in office.

FILE - New York City Mayor Rudolph Giuliani leads New York Gov. George Pataki, left, and Sen. Hillary Clinton, D-N.Y., on a tour of the site of the World Trade Center disaster, Sept. 12, 2001.

As his final term as mayor was coming to an end, the 9/11 attacks put a spotlight on Giuliani, as he led efforts to recover from the shattering terrorist attacks. He won near-unanimous praise for his handling of the attacks’ aftermath, earning the nickname “America’s Mayor,” and soon afterward left public office to launch Giuliani Partners, a security consulting firm.

He briefly returned to public view in 2008, with a failed bid to win the Republican presidential nomination. Though he was thought to be considering other races, including for the New York governorship and another presidential run, Giuliani has not been a candidate for office in more than a decade.