Complex sentence: In 1857 he became High Commissioner to China and travelled to China and Japan in 1858-59, where he led the bombing of Canton and oversaw the end of the Second Opium War by signing the Treaties of Tianjin on 26 June 1858.
Split into simpler sentences: In 1857 he became High Commissioner to China and travelled to China and Japan in 1858-59, where he led the bombing of Canton. He oversaw the end of the Second Opium War by signing the Treaties of Tianjin on 26 June 1858.