Former German President Horst Köhler died in Berlin Saturday morning after a short illness, the office of current German President Frank-Walter Steinmeier said in a statement.

Köhler, who was president between 2004 and 2010, was surrounded by family at the time of his death, according to the statement. He was 81.

Steinmeier says Germany lost a 'deep, thoughtful' person

"We have lost a highly esteemed and extremely popular person who achieved great things —  for our country and in the world," Steinmeier wrote in a letter of condolence that he sent to Köhler's widow, Eva Luise Köhler.

"When Horst Köhler was elected Federal President in 2004, he was virtually unknown to a wider public," Steinmeier wrote on Saturday, adding "How quickly he then gained so much recognition and sympathy"

Everything "he said and did was usually preceded by long and deep reflections and discussions," Steinmeier wrote.

Who was Horst Köhler?

Köhler was an economist and a former managing director at the International Monetary Fund (IMF) before turning to politics and taking the mostly ceremonial office of German president. 

He was a relative newcomer, and when he became president, Germany's Bild tabloid greeted him with the headline "Horst Who?"

He was also a close ally of former Chancellor Angela Merkel who lobbied hard for his presidency in 2004. 

Köhler eventually built high popularity ratings once in the job, but his presidency came to an end after he resigned in 2010 over criticism following controversial comments he made during a trip to Afghanistan. 

In the years after office, Köhler remained engaged in works in foreign affairs, projects concerning development in Africa, and climate change.

rm/wmr (AP, dpa, KNA)