Irena Karpa, 33, a writer and musician who is popular among young Ukrainians, shares the optimism, and the relief that her country was shaking off the old order. “For a very long time, I thought I was alone,” she said. “Finally, it all happened — people stopped being so passive.”

She took her children, ages 2 and 3, to the Maidan, the square in Kiev at the center of the protests that ultimately drove Mr. Yanukovych out, to explain what was happening, and she discovered to her delight that “I was by no means the most radical parent in our kindergarten.”

Her parents’ generation, she said, focused on their private lives as the Soviet Union came apart in 1991 and Ukraine gained what has proved to be a messy independence. Business was conducted on an “I know you, you know me” basis, she said, stunting the growth of private companies and institutions. Now “the Soviet Union finally collapsed,” Ms. Karpa said. “It is a pleasure to live in another historic moment.”

One lesson she had learned, she said, was the importance of voting. Like many of her contemporaries, she did not bother to cast a ballot in the 2010 election and regretted the result. “I say now, it was my own fault Yanukovych got elected,” she said. “Bad power is elected by good people who do not vote.”

Like dozens of other young Ukrainians heard from or interviewed in Kiev and Donetsk over the past two weeks, Ms. Karpa said she was determined now to shape her own future and speak her mind. Outside observers have noted the mood as well: Mikhail B. Khodorkovsky, the Russian tycoon and political opponent of President Vladimir V. Putin who was released in December after 10 years in prison, said he saw in Ukraine “a readiness to take responsibility for one’s fate.”