The Royal Danish Mail Service in the 1820s was characterized by a number of postal routes running through the Kingdom of Denmark and the duchies of Schleswig and Holstein.

[1] But in 1827 the mood changed and the public was allowed to send mail with the steamship Prindsesse Wilhelmine to Lübeck, and later with the Dania to Jutland, if the envelopes were marked accordingly.

[2] The Danish state set up a committee to inquire "if a steamship travelling the Great Belt could manage a storm, and if it could sail in winter, when there was no ice, but still cold enough for water splashing over the ship, to freeze on its deck and sides, possibly hindering the work of the paddles and machinery."

In May 1827 came the reply, stating "that only a hurricane could delay or stop the ship, and the water running over the vessel during two hours of sailing in freezing weather would not compromise the journey."

The choice of builder might have been influenced by the fact that in 1826 Graham had delivered two paddle steamers, Watersprite and Wizard, to the British Royal Mail.

In spite of his naval rank, Christensen — his first name also spelled Lauritz — had not done active service since 1814, and his status as a reservist had enabled him to do business in the East Indies from 1816 til 1826.

[9] In 1844, the steamship Kronprins Frederik Carl Christian entered service on the Belt, leaving the Mercurius to do miscellaneous tasks.