Karl Gützlaff
In 1846, Hamberg was sent to China, where he arrived on March 19 the following year and started to work in the Guangdong mission, where he worked to convert members from the Hakka community. He also worked out a draft of the first description of the Hakka dialect, which provided the foundation to D. MacIver's Hakka dictionary. Hamberg initially worked under the influential German missionary Karl Gützlaff, but Hamberg gradually grew skeptical of Gützlaff's strategy of mass conversions; instead he advocated a more cautious approach, which in due course would bring him into conflict with Gützlaff and with the Basel Mission. After the death of Gützlaff, Hamberg was vindicated and he continued to work under the Basel Mission.