Younghusband was born in India to British parents, and was educated in England. His first expedition to the Himalayas was in 1884, when he went to Afghanistan and Kashmir for the British Army. In 1886, he went to Manchuria, China, and returned to India overland with Colonel Mark Bell. They traveled over 1,250 miles (they split up for part of the journey), crossing the Gobi Desert, the Taklamakan Desert, the Karakorum Mountains, and the Himalayas, returning to India at Rawalpindi.

In 1889, Younghusband returned to the Karakorum Mountains for the Army and later became an official of the Indian Foreign Department in order to stop the Russians (who were exploring the border regions near Afghanistan and Tadzhikistan). In 1890, he traveled with Sir George McCartney on a diplomatic trip to central Asia. Leading an anti-Russian 1903 trip to Tibet, Younghusband was accompanied by 3,000 troops commanded by Sir James MacDonald. Along the way, they explored the Brahmaputra River and the Sutlej River.

Younghusband wrote of his adventures in the books: Heart of a Continent (1896), India and Tibet (1910), and The Epic of Mount Everest (1926).