You're reading: New York Times: Key dates at the center of the Ukraine matter

The origins of the impeachment inquiry engulfing President Trump and his administration go back to the election this spring of a new Ukrainian president, Volodymyr Zelensky. Over the next five months, White House emissaries pressured Mr. Zelensky to announce that Ukraine would investigate two matters: Burisma Holdings, a Ukrainian gas company that hired Hunter Biden, the younger son of former Vice President Joseph R. Biden Jr., and whether Ukraine had meddled in the 2016 American presidential election.

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