MOSCOW — In the far east, the teachers went on strike. In central Russia, it was the employees of a metallurgical plant. In St. Petersburg, autoworkers laid down their tools. And at a remote construction site in Siberia, laborers painted their complaints in gigantic white letters on the roofs of their dormitories.

“Dear Putin, V.V.,” the message said. “Four months without pay.”

After months of frustration with an economy sagging under the weight of international sanctions and falling energy prices, workers across Russia are starting to protest unpaid wages and go on strike, in the first nationwide backlash against President Vladimir V. Putin’s economic policies.

The protests have been wildcat actions for the most part, as organized labor never emerged as a strong political or economic force in modern Russia. Under the Soviets, labor unions had been essentially incorporated into management.

Russian companies tend to avoid laying off workers in a downturn to limit severance payments — or to evade the wrath of officials trying to minimize unemployment in their districts. So with the Russian economy expected to contract this year and next, many workers are going unpaid or being sent away from their factories for a few days at a time of unwanted “vacations.”