ISTANBUL — Seventeen journalists and executives of the last prominent independent newspaper in Turkey, Cumhuriyet, went on trial in Istanbul on Monday, accused of aiding terrorist organizations under a government crackdown against opponents since a failed coup last year.

Two other defendants, a jailed teacher prominent on social media and a former correspondent based in the United States, have been included in the same indictment. The trial, which is expected to come to a provisional decision on Friday, is being seen as a test case for the freedom of the press in Turkey, now the biggest jailer of journalists in the world.

“The picture is clear,” Akin Atalay, the newspaper’s chief executive, a former lawyer, told a sweltering hot courtroom packed with journalist colleagues, families of defendants and international monitors.

“One aim is to silence Cumhuriyet or seize it,” he said. “The second aim is to show other journalists their fate and in practice what will happen if they write what the government does not like.”