Here is everything you need to know, to-date.
- April 2014: Hunter Biden joined Ukrainian energy company Burisma.
- August 2014: Ukrainian Prosecutor General Vitaly Yarema opened a corruption investigation about Burisma.
- Fall 2015/Winter 2015–2016: Then-Vice President Joe Biden first made a public issue out of alleged prosecutor-related corruption in Ukraine.
- February 2016: Ukrainian energy company Burisma, which had Hunter Biden as a board member at the time, sought to utilize Biden’s stature as a means to secure a U.S. State Department meeting.
- March 2016: Then-Vice President Joe Biden pressured Ukraine to fire the prosecutor involved with investigating Burisma.
- June 2017: Rudy Giuliani visited Ukraine and met with Ukrainian President Petro Poroshenko and Ukrainian Prosecutor General Yuriy Lutsenko.
- January 2018: Joe Biden was filmed bragging about how he forced the firing of a Ukrainian prosecutor he did not like by threatening to withhold foreign aid to Ukraine.
- August 2018: Giuliani was hired by a company run by Ukrainian business tycoon Lev Parnas.
- Later 2018: Giuliani pressured Lutsenko to open corruption-related investigations about the Bidens and Burisma.
- January 2019: Giuliani met multiple times with Lutsenko and, according to The New York Times, allegedly pushed Lutsenko on the Bidens, Burisma, and then-U.S. Ambassador to Ukraine Marie Yovanovitch.
- March 2019: Lutsenko opened two investigations — one on the Bidens and one on Burisma. The Times alleged that Lutsenko also accused Yovanovitch of corruption.
- April 2019: Trump reportedly told Fox News host Sean Hannity that Attorney General William Barr might investigate allegations about Ukrainian interference in the 2016 presidential election.
- May 2019: Yovanovitch resigned as U.S. ambassador to Ukraine.
- May 2019: The New York Times reported on an upcoming Rudy Giuliani trip to Ukraine.
- May 2019: Giuliani expressed his belief in the theory that Ukraine actively assisted the Hillary Clinton campaign during the 2016 presidential election.
- June 2019: Giuliani tweeted that Ukraine was “abused by Hillary and Obama people.”
- July 25, 2019: Now-infamous phone call took place between Trump and Ukrainian president Volodymyr Zelensky.
- September 24, 2019: Transcript of phone call released between Trump and Ukrainian president Volodymyr Zelensky.
- September 24, 2019: House Speaker Nancy Pelosi (D-CA) announced that House Democrats would seek to open an impeachment inquiry against President Trump.
- September 26, 2019: Whistleblower complaint about the Trump-Zelensky phone call revealed.
- October 2, 2019: Revelation that Rep. Adam Schiff’s (D-CA) office had been in contact with the whistleblower.
- October 17, 2019: Written testimony of U.S. ambassador to the European Union Gordon Sondland includes: “President Trump was skeptical that Ukraine was serious about reforms and anti-corruption, and he directed those of us present at the meeting to talk to Mr. Giuliani, his personal attorney, about his concerns. It was apparent to all of us that the key to changing the President’s mind on Ukraine was Mr. Giuliani.”
- October 22, 2019: Written testimony of top U.S. diplomat to Ukraine Bill Taylor notes: By mid-July, it was becoming clear to me that the meeting President Zelenskyy wanted was conditioned on the investigations of Burisma and alleged Ukrainian interference in the 2016 U.S. elections. It was also clear that this condition was driven by the irregular policy channel I had come to understand was guided by Mr. Giuliani.”
- October 29, 2019: Lt. Col. Alexander Vindman, who serves on the U.S. National Security Council, testified that the White House’s released transcript of the Trump-Zelensky phone call had crucial omissions with respect to the Bidens.
- October 31, 2019: House voted to establish the procedural rules governing the impeachment of President Trump.