A man of strength, Swedish diplomat and writer Dag Hjalmar Agne Carl Hammarskjöld (1905-1961) transformed the United Nations into a political international force and initiated its peacekeeping role.

He once said, "Each day the first day: Each day a life."

A man of character and optimism, he also advised: "Never look down to test the ground before taking your next step; only he who keeps his eye fixed on the horizon will find the right road."

Born on this day in Jonkoping, Sweden, he was the son of the Swedish Prime Minister during World War I. From his father, Hammarskjöld said he "inherited a belief that no life was more satisfactory than one of selfless service to your country - or humanity."

Elected as Secretary-General of the United Nations in 1953, he said, "Nobody...can serve in that capacity without a sense of gratitude for a task as deeply rewarding as it is exacting."

In 1961, the diplomat was on a peacekeeping mission to the Congo when he died in a plane crash. Later that year, he received the Nobel Prize Prize for his commitment to peace. Three years later, his unique journal, Markings (Vägmärken), was published.

Markings, a spiritual diary and autobiography, looked at Hammarskjöld's negotiations with himself and with God. "The more faithfully you listen to the voice within you," he wrote, "the better you will hear what is sounding outside."

Hammarskjöld once celebrated: "For what has been -- thanks! For what shall be -- yes!"

More Dag HAMMARSKJOLD Quotations

You have the strength to handle anything in life.