SIMFEROPOL, Ukraine — Early this month, Russian soldiers took up positions at the television transmission center here in the capital of the Ukrainian region of Crimea. Their arrival was part of a broad effort to muffle dissent over the Kremlin-backed project to guide Crimea through a swift secession from Ukraine.

Several days later, the soldiers handed over their post to a pro-secession militia. Some of these men carried whips. Technicians took the next step, removing Ukrainian networks from the air and replacing them with state-controlled channels from Moscow.

By last week, the transformation was complete. The media hub’s entrance was adorned with bright flags and banners. A young woman cheerfully urged journalists to be seated for a pro-secession news conference at what she now called, with a confident Orwellian flair, the Open Press Center — no matter that several television station signals had just been unplugged.

The switchover was one step in the abrupt shift in civic life on the Crimean Peninsula, where open dissent has been suppressed by the implicit threat of force. In a matter of days, the Kremlin has succeeded in recreating the constrained conditions of Russia’s own civic sphere in Crimea.