William Taylor, the top American diplomat in Ukraine, and George Kent, a senior State Department official, were the first of what is expected to be a parade of witnesses over the next 10 days. Some takeaways from Wednesday’s hearing:

In a new detail, Mr. Taylor testified that one of his aides had overheard a phone call involving Mr. Trump and Gordon Sondland, the ambassador to the European Union, in which the president asked about “the investigations.” When the aide asked about Mr. Trump’s thoughts on Ukraine, Mr. Sondland said the president cared more about “investigations of Biden.”

Mr. Kent said that efforts to pressure President Volodymyr Zelensky of Ukraine “were now infecting U.S. engagement with Ukraine, leveraging President Zelensky’s desire for a White House meeting.”

Republicans dismissed Mr. Taylor and Mr. Kent, both veteran diplomats, as representatives of a “politicized bureaucracy” without firsthand knowledge of Mr. Trump’s actions.

Catch up: Our video covers the highlights of the five-hour hearing in about four minutes.

Quotable: “I am not here to take one side or another or to advocate for any particular outcome,” Mr. Taylor said. “My sole purpose is to provide facts.”

Closer look: Mr. Taylor, who did most of the talking, and the bow-tied Mr. Kent embodied the traditional Washington that Mr. Trump has rejected. Read more about the scene on Capitol Hill.

News analysis: “It was not clear that minds were changed,” our chief White House correspondent writes. “But whether or not voters were watching , history certainly was.”

Reaction: Mr. Trump said he had been too busy to watch the hearing but dismissed it as “a hoax.” He welcomed President Recep Tayyip Erdogan of Turkey to the White House, a month after the country’s incursion into Syria scrambled U.S. policy in the Middle East.

“The Daily”: Today’s episode is about the hearing.

Another angle: The drama in Washington is weakening Mr. Zelensky’s position as he seeks to end his country’s conflict with Russian-backed separatists.