Sellapan Ramanathan, Singapore’s sixth and longest-serving president, died Aug. 22 at a hospital in Singapore. He was 92.

The government announced the death. Widely known as S.R. Nathan, he had been hospitalized in critical condition after suffering a stroke July 31. It was his second stroke in less than two years.

Mr. Ramanathan served two terms as Singapore’s head of state from 1999 to 2011 before being succeeded by Tony Tan Keng Yam.

He had held top positions in the civil service and was appointed high commissioner to Malaysia in 1988. From 1990 to 1996, Mr. Ramanathan served as Singapore’s ambassador to the United States.

Mr. Ramanathan, of Tamil heritage, was born in Singapore on July 3, 1924. He spent several years in Malaysia, where his father worked as a legal clerk for a company that serviced rubber plantations. Because of a slump in rubber prices, his father lost his job and fell into severe debt. Mr. Ramanathan was 8 when his father, reduced to working in a granite quarry, committed suicide.

Britain's Queen Elizabeth II with Singapore's President S.R. Nathan after a welcome ceremony held during her arrival in 2006 at the Istana, or presidential palace, in Singapore. (Wong Maye-E/AP)

“All I remember was, I kept asking the people around me, ‘When is my father coming home?’ ‘Where is my father?’ ” he later told the Straits Times of Singapore.

He said he left home at 16 after a fight with his mother and landed work as an office boy. He learned Japanese during World War II and survived the occupation. He later attended college on a scholarship while working in a public works job.

He continued a slow advancement through the government bureaucracy, becoming deputy secretary in the Foreign Affairs Ministry in the 1970s, followed by a high-level job in the Defense Ministry.

Survivors include his wife, the former Urmila Nandey; two children; and three grandchildren.