Gyorgy Konrad, a writer and sociologist who was a major figure in Hungary’s dissident movement under Communist rule, died on Friday at his home in Budapest. He was 86.

His family confirmed the death and said he had been gravely ill.

Known internationally for books like his novel “The Case Worker” (1969) and his memoir “A Guest in My Own Country: A Hungarian Life” (2007), Mr. Konrad was considered a steadfast advocate for individual freedom. The English translations of most of his books rendered his first name as George.

After the government lifted a publication ban on him, Mr. Konrad described himself in a 1990 article this way:

“A 57-year-old novelist and essayist. Hungarian in language and citizenship. Of the Jewish faith. The father of four children from two marriages. Wardrobe rather modest, but does own several typewriters.”

He later had a fifth child, born in 1994.

Mr. Konrad was a beloved figure with a soft-spoken radicalism that allowed him to bridge generation gaps. Under Communism, with its emphasis on subjugation of the individual to the collective, his ideas about the sovereignty of all humans being were considered subversive.