She and her new husband sailed to Hawaii in 1832, part of the fifth company of missionaries sent by the American Board of Commissioners for Foreign Missions (ABCFM).
[2][3] Most of their work was located on the north shore of Oahu, at Waialua, where they were supported by High Chief Gideon Peleʻioholani Laʻanui.
[4][5] They founded the Liliʻuokalani Protestant Church, on lands donated by Laʻanui,[5][6] where she led the singing "with energy and precision",[7] and a school for teachers, where she taught.
[8] Ursula Newell Emerson drew some of the earliest surviving manuscript maps of Hawaiʻi, in 1833, for teaching use; they are now in the collection of the Hawaiian Historical Society.
[14] In the 1920s, stamps that Ursula Newell Emerson may have sent to a childhood friend in New England became the subject of controversy and lawsuits, as uncancelled missionary postage from Hawaii was a rare find for collectors.