KIEV, Ukraine — The last time Oleg Tyagnibok was a member of Ukraine’s Parliament, his colleagues kicked him out over a fiery speech in which he described how Ukrainians, during World War II, bravely fought Muscovites, Germans, Jews “and other scum,” and then used slurs to refer to the “Jewish-Russian mafia, which rules in Ukraine.”

Eight years later, Mr. Tyagnibok is preparing to return to Parliament, not as a lone member of a broader coalition, as he was when he was ejected, but as the leader of Svoboda, the ultranationalist, right-wing party that will control 38 of 450 seats, or about 8.5 percent of the national legislature.

Svoboda’s surprising show of strength in the Oct. 29 election — polls had predicted that the party would fail to meet the 5 percent threshold to enter Parliament — has stirred alarm, including warnings from Israel about the rise of anti-Semitism and xenophobia in Ukraine, a former Soviet republic and a place with a firsthand knowledge of ethnic violence and genocide.

But in an interview in the downtown office building that Svoboda shares with an insurance company and a dental clinic named Smile, Mr. Tyagnibok said that fear of his party was misplaced and the accusations of racism and extremism unfounded.