A young woman sings the Ukrainian national anthem during pro-Ukrainian rally in Simferopol in Crimea on Sunday. (Alexey Furman/EPA)

Barely a mile apart in this Crimean capital Sunday, two rallies — one pro-Russian, the other pro-Ukrainian — drew crowds that represented different age groups and offered sharply contrasting portraits of life today in a region that stands on the brink of sundering along ethnic, ideological and generational lines.

In a shaded park named for the 19th-century poet Taras Shevchenko, there was a gathering of hundreds of people who had been brought up in an independent, post-Soviet Ukraine: young men in jeans, young women in thigh boots or with garlanded braids. They carried balloons, recited Shevchenko’s poems and sang anthems about the glories of Ukraine to a fast, pumped-up beat.

“I am a Ukrainian patriot. I grew up here, and I don’t want to belong to another country,” said Alina Shazhko, 23, an English teacher. “We sacrificed so much for our freedom, and we don’t want to lose it.”

Nearby, on a plaza dominated by a statue of the communist leader Vladimir Lenin, hundreds of older workers, housewives and veterans cheered entertainers who sang stirring military anthems from World War II and the Soviet conflict in Afghanistan. They later applauded speakers who called for their region to “return home to the Russian motherland.”

“For 23 years, we have been humiliated and mistreated, and now the fascists have taken over in Kiev. When we go back to Russia, we will have peace and be able to speak our mother tongue again, and we won’t have to worry about losing our pensions,” said a factory worker in her late 50s who gave her name as Katya. Other women nearby nodded vehemently in agreement.

There were no reports of violence between the rally-goers, only competing shouts of “Ross-i-ya” and “U-kraine” as they crossed paths at subway stops or careered through the city in convoys afterward, honking.

But there was a notable difference between the structure of both events and the security forces sent to keep order. Troops in camouflage garb, members of informal “self-defense forces,” and Cossack guards in thick coats and caps surrounded the pro-Russian rally, which featured a raised stage with a military band and entertainers.

The pro-Ukrainian rally was more informal, with recorded songs and a small contingent of local uniformed police, most of the officers just as young as the crowd. But there were reports that two rally organizers had been detained before they reached the site.

Although the demonstrators work, shop and socialize in the same crowded city of 200,000, it seemed as if the mostly older, pro-Russian loyalists and the mostly younger, pro-Ukrainian supporters inhabited two distant worlds.

From their contradictory versions of regional history, it appeared that a once-shared narrative of post-independence harmony had rapidly hardened into mutual blame and propaganda. People at both events said they feared that ethnic clashes or even civil war could erupt.

The pro-Russian demonstrators warned that “revolutionary fascist thugs” from Kiev were threatening the safety of Crimea, an autonomous region. Crimea joined Ukraine in 1954 when the nation was still a part of the Soviet Union. Pro-Ukrainian activists warned that “foreign troops” from Russia were invading their land.

Marina Slobodenska, 32, a lawyer from Kiev who participated in the protests there that led to 82 deaths and the ouster of Ukraine’s pro-Russian president in February, said she did not object to the March 16 referendum on whether Crimea should return to Russia. But she warned that voters should “remember the past and think twice” about what they wish for. “If Russia gets in power again,” she asked, “will it truly serve the people?”

But in the jammed plaza nearby, older couples beamed and clapped with delight as performers in Russian sailor uniforms danced and sang patriotic ballads. People poked donations into boxes for veterans of the 1980s Afghanistan war. “We will go straight to heaven, for Russia, for freedom,” they sang.

Many ethnic Russians described feeling belittled since Ukraine gained independence in 1991 with the fall of the Soviet Union, and several said they longed to recover the pride they had felt as heirs to a once-great Slavic empire and a revolution that defined their lifetimes. Hammer-and-sickle banners waved high above the crowd, and no one spoke of the purges and famines that marked the early Soviet years.

After the entertainment, a succession of politicians spoke about returning to the bosom of the Russian motherland. One speaker, Vetalina Zoss, exhorted the audience to vote in the referendum, saying, “We are not cattle. No one can dictate which language we speak, which heroes we honor. It is up to us to write the future of Crimea in ink or blood.”

At Shevchenko Park, not everyone was young. Alexi Tyntyninko, 83, a retired crane operator, trembled as he recalled the horrors of war and famine that his people had endured.

“Ukraine is a beautiful place, and I helped to build so many schools and homes and clinics here,” Tyntyninko said. “If anyone comes here to destroy it, God save us from them.”